You are viewing the version of this documentation from Perl 5.41.7. This is a development version of Perl.

CONTENTS

NAME

Config - access Perl configuration information

SYNOPSIS

use Config;
if ($Config{usethreads}) {
    print "has thread support\n"
}

use Config qw(myconfig config_sh config_vars config_re);

print myconfig();

print config_sh();

print config_re();

config_vars(qw(osname archname));

DESCRIPTION

The Config module contains all the information that was available to the Configure program at Perl build time (over 900 values).

Shell variables from the config.sh file (written by Configure) are stored in the readonly-variable %Config, indexed by their names.

Values stored in config.sh as 'undef' are returned as undefined values. The perl exists function can be used to check if a named variable exists.

For a description of the variables, please have a look at the Glossary file, as written in the Porting folder, or use the url: https://github.com/Perl/perl5/blob/blead/Porting/Glossary

myconfig()

Returns a textual summary of the major perl configuration values. See also -V in "Command Switches" in perlrun.

config_sh()

Returns the entire perl configuration information in the form of the original config.sh shell variable assignment script.

config_re($regex)

Like config_sh() but returns, as a list, only the config entries who's names match the $regex.

config_vars(@names)

Prints to STDOUT the values of the named configuration variable. Each is printed on a separate line in the form:

name='value';

Names which are unknown are output as name='UNKNOWN';. See also -V:name in "Command Switches" in perlrun.

bincompat_options()

Returns a list of C pre-processor options used when compiling this perl binary, which affect its binary compatibility with extensions. bincompat_options() and non_bincompat_options() are shown together in the output of perl -V as Compile-time options.

non_bincompat_options()

Returns a list of C pre-processor options used when compiling this perl binary, which do not affect binary compatibility with extensions.

compile_date()

Returns the compile date (as a string), equivalent to what is shown by perl -V

local_patches()

Returns a list of the names of locally applied patches, equivalent to what is shown by perl -V.

header_files()

Returns a list of the header files that should be used as dependencies for XS code, for this version of Perl on this platform.

EXAMPLE

Here's a more sophisticated example of using %Config:

use Config;
use strict;

my %sig_num;
my @sig_name;
unless($Config{sig_name} && $Config{sig_num}) {
    die "No sigs?";
} else {
    my @names = split ' ', $Config{sig_name};
    @sig_num{@names} = split ' ', $Config{sig_num};
    foreach (@names) {
        $sig_name[$sig_num{$_}] ||= $_;
    }
}

print "signal #17 = $sig_name[17]\n";
if ($sig_num{ALRM}) {
    print "SIGALRM is $sig_num{ALRM}\n";
}

WARNING

Because this information is not stored within the perl executable itself it is possible (but unlikely) that the information does not relate to the actual perl binary which is being used to access it.

The Config module is installed into the architecture and version specific library directory ($Config{installarchlib}) and it checks the perl version number when loaded.

The values stored in config.sh may be either single-quoted or double-quoted. Double-quoted strings are handy for those cases where you need to include escape sequences in the strings. To avoid runtime variable interpolation, any $ and @ characters are replaced by \$ and \@, respectively. This isn't foolproof, of course, so don't embed \$ or \@ in double-quoted strings unless you're willing to deal with the consequences. (The slashes will end up escaped and the $ or @ will trigger variable interpolation)

GLOSSARY

Most Config variables are determined by the Configure script on platforms supported by it (which is most UNIX platforms). Some platforms have custom-made Config variables, and may thus not have some of the variables described below, or may have extraneous variables specific to that particular port. See the port specific documentation in such cases.

P

PERL_API_REVISION

From patchlevel.h:

This number describes the earliest compatible PERL_REVISION of Perl (compatibility here being defined as sufficient binary/API compatibility to run XS code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_API_SUBVERSION

From patchlevel.h:

This number describes the earliest compatible PERL_SUBVERSION of Perl (compatibility here being defined as sufficient binary/API compatibility to run XS code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_API_VERSION

From patchlevel.h:

This number describes the earliest compatible PERL_VERSION of Perl (compatibility here being defined as sufficient binary/API compatibility to run XS code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_CONFIG_SH

From Oldsyms.U:

This is set to true in config.sh so that a shell script sourcing config.sh can tell if it has been sourced already.

PERL_PATCHLEVEL

From Oldsyms.U:

This symbol reflects the patchlevel, if available. Will usually come from the .patch file, which is available when the perl source tree was fetched with rsync.

PERL_REVISION

From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 5. This value is manually set in patchlevel.h

PERL_SUBVERSION

From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 2. Values greater than 50 represent potentially unstable development subversions. This value is manually set in patchlevel.h

PERL_VERSION

From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 6. This value is manually set in patchlevel.h

_

_a

From Unix.U:

This variable defines the extension used for ordinary library files. For unix, it is .a. The . is included. Other possible values include .lib.

_exe

From Unix.U:

This variable defines the extension used for executable files. DJGPP, Cygwin and OS/2 use .exe. Stratus VOS uses .pm. On operating systems which do not require a specific extension for executable files, this variable is empty.

_o

From Unix.U:

This variable defines the extension used for object files. For unix, it is .o. The . is included. Other possible values include .obj.

a

afs

From afs.U:

This variable is set to true if AFS (Andrew File System) is used on the system, false otherwise. It is possible to override this with a hint value or command line option, but you'd better know what you are doing.

afsroot

From afs.U:

This variable is by default set to /afs. In the unlikely case this is not the correct root, it is possible to override this with a hint value or command line option. This will be used in subsequent tests for AFSness in the configure and test process.

alignbytes

From alignbytes.U:

This variable holds the number of bytes required to align a double-- or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety.

aphostname

From d_gethname.U:

This variable contains the command which can be used to compute the host name. The command is fully qualified by its absolute path, to make it safe when used by a process with super-user privileges.

api_revision

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_revision is the 5. Prior to 5.5.640, the format was a floating point number, like 5.00563.

perl.c:incpush() and lib/lib.pm will automatically search in $sitelib/.. for older directories back to the limit specified by these api_ variables. This is only useful if you have a perl library directory tree structured like the default one. See INSTALL for how this works. The versioned site_perl directory was introduced in 5.005, so that is the lowest possible value. The version list appropriate for the current system is determined in inc_version_list.U.

XXX To do: Since compatibility can depend on compile time options (such as bincompat, longlong, etc.) it should (perhaps) be set by Configure, but currently it isn't. Currently, we read a hard-wired value from patchlevel.h. Perhaps what we ought to do is take the hard-wired value from patchlevel.h but then modify it if the current Configure options warrant. patchlevel.h then would use an #ifdef guard.

api_subversion

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_subversion is the 1. See api_revision for full details.

api_version

From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_version is the 6. See api_revision for full details. As a special case, 5.5.0 is rendered in the old-style as 5.005. (In the 5.005_0x maintenance series, this was the only versioned directory in $sitelib.)

api_versionstring

From patchlevel.U:

This variable combines api_revision, api_version, and api_subversion in a format such as 5.6.1 (or 5_6_1) suitable for use as a directory name. This is filesystem dependent.

ar

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ar program. After Configure runs, the value is reset to a plain ar and is not useful.

archlib

From archlib.U:

This variable holds the name of the directory in which the user wants to put architecture-dependent public library files for $package. It is most often a local directory such as /usr/local/lib. Programs using this variable must be prepared to deal with filename expansion.

archlibexp

From archlib.U:

This variable is the same as the archlib variable, but is filename expanded at configuration time, for convenient use.

archname

From archname.U:

This variable is a short name to characterize the current architecture. It is used mainly to construct the default archlib.

archname64

From use64bits.U:

This variable is used for the 64-bitness part of $archname.

archobjs

From Unix.U:

This variable defines any additional objects that must be linked in with the program on this architecture. On unix, it is usually empty. It is typically used to include emulations of unix calls or other facilities. For perl on OS/2, for example, this would include os2/os2.obj.

asctime_r_proto

From d_asctime_r.U:

This variable encodes the prototype of asctime_r. It is zero if d_asctime_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_asctime_r is defined.

awk

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the awk program. After Configure runs, the value is reset to a plain awk and is not useful.

b

baserev

From baserev.U:

The base revision level of this package, from the .package file.

bash

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

bin

From bin.U:

This variable holds the name of the directory in which the user wants to put publicly executable images for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution.

bin_ELF

From dlsrc.U:

This variable saves the result from configure if generated binaries are in ELF format. Only set to defined when the test has actually been performed, and the result was positive.

binexp

From bin.U:

This is the same as the bin variable, but is filename expanded at configuration time, for use in your makefiles.

bison

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the bison program. After Configure runs, the value is reset to a plain bison and is not useful.

byacc

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the byacc program. After Configure runs, the value is reset to a plain byacc and is not useful.

byteorder

From byteorder.U:

This variable holds the byte order in a UV. In the following, larger digits indicate more significance. The variable byteorder is either 4321 on a big-endian machine, or 1234 on a little-endian, or 87654321 on a Cray ... or 3412 with weird order !

c

c

From n.U:

This variable contains the \c string if that is what causes the echo command to suppress newline. Otherwise it is null. Correct usage is $echo $n "prompt for a question: $c".

castflags

From d_castneg.U:

This variable contains a flag that precise difficulties the compiler has casting odd floating values to unsigned long: 0 = ok 1 = couldn't cast < 0 2 = couldn't cast >= 0x80000000 4 = couldn't cast in argument expression list

cat

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cat program. After Configure runs, the value is reset to a plain cat and is not useful.

cc

From cc.U:

This variable holds the name of a command to execute a C compiler which can resolve multiple global references that happen to have the same name. Usual values are cc and gcc. Fervent ANSI compilers may be called c89. AIX has xlc.

cccdlflags

From dlsrc.U:

This variable contains any special flags that might need to be passed with cc -c to compile modules to be used to create a shared library that will be used for dynamic loading. For hpux, this should be +z. It is up to the makefile to use it.

ccdlflags

From dlsrc.U:

This variable contains any special flags that might need to be passed to cc to link with a shared library for dynamic loading. It is up to the makefile to use it. For sunos 4.1, it should be empty.

ccflags

From ccflags.U:

This variable contains any additional C compiler flags desired by the user. It is up to the Makefile to use this.

ccflags_uselargefiles

From uselfs.U:

This variable contains the compiler flags needed by large file builds and added to ccflags by hints files.

ccname

From Checkcc.U:

This can set either by hints files or by Configure. If using gcc, this is gcc, and if not, usually equal to cc, unimpressive, no? Some platforms, however, make good use of this by storing the flavor of the C compiler being used here. For example if using the Sun WorkShop suite, ccname will be workshop.

ccsymbols

From Cppsym.U:

The variable contains the symbols defined by the C compiler alone. The symbols defined by cpp or by cc when it calls cpp are not in this list, see cppsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

ccversion

From Checkcc.U:

This can set either by hints files or by Configure. If using a (non-gcc) vendor cc, this variable may contain a version for the compiler.

cf_by

From cf_who.U:

Login name of the person who ran the Configure script and answered the questions. This is used to tag both config.sh and config_h.SH.

cf_email

From cf_email.U:

Electronic mail address of the person who ran Configure. This can be used by units that require the user's e-mail, like MailList.U.

cf_time

From cf_who.U:

Holds the output of the date command when the configuration file was produced. This is used to tag both config.sh and config_h.SH.

charbits

From charsize.U:

This variable contains the value of the CHARBITS symbol, which indicates to the C program how many bits there are in a character.

charsize

From charsize.U:

This variable contains the value of the CHARSIZE symbol, which indicates to the C program how many bytes there are in a character.

chgrp

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

chmod

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the chmod program. After Configure runs, the value is reset to a plain chmod and is not useful.

chown

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

clocktype

From d_times.U:

This variable holds the type returned by times(). It can be long, or clock_t on BSD sites (in which case <sys/types.h> should be included).

comm

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the comm program. After Configure runs, the value is reset to a plain comm and is not useful.

compiler_warning

From compiler_warning.U:

This variable holds the command to check if the file specified as a parameter contains a compiler warning

compress

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

config_arg0

From Options.U:

This variable contains the string used to invoke the Configure command, as reported by the shell in the $0 variable.

config_argc

From Options.U:

This variable contains the number of command-line arguments passed to Configure, as reported by the shell in the $# variable. The individual arguments are stored as variables config_arg1, config_arg2, etc.

config_args

From Options.U:

This variable contains a single string giving the command-line arguments passed to Configure. Spaces within arguments, quotes, and escaped characters are not correctly preserved. To reconstruct the command line, you must assemble the individual command line pieces, given in config_arg[0-9]*.

contains

From contains.U:

This variable holds the command to do a grep with a proper return status. On most sane systems it is simply grep. On insane systems it is a grep followed by a cat followed by a test. This variable is primarily for the use of other Configure units.

cp

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cp program. After Configure runs, the value is reset to a plain cp and is not useful.

cpio

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

cpp

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cpp program. After Configure runs, the value is reset to a plain cpp and is not useful.

cpp_stuff

From cpp_stuff.U:

This variable contains an identification of the concatenation mechanism used by the C preprocessor.

cppccsymbols

From Cppsym.U:

The variable contains the symbols defined by the C compiler when it calls cpp. The symbols defined by the cc alone or cpp alone are not in this list, see ccsymbols and cppsymbols. The list is a space-separated list of symbol=value tokens.

cppflags

From ccflags.U:

This variable holds the flags that will be passed to the C pre- processor. It is up to the Makefile to use it.

cpplast

From cppstdin.U:

This variable has the same functionality as cppminus, only it applies to cpprun and not cppstdin.

cppminus

From cppstdin.U:

This variable contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This variable will have the value - if cppstdin needs a minus to specify standard input, otherwise the value is "".

cpprun

From cppstdin.U:

This variable contains the command which will invoke a C preprocessor on standard input and put the output to stdout. It is guaranteed not to be a wrapper and may be a null string if no preprocessor can be made directly available. This preprocessor might be different from the one used by the C compiler. Don't forget to append cpplast after the preprocessor options.

cppstdin

From cppstdin.U:

This variable contains the command which will invoke the C preprocessor on standard input and put the output to stdout. It is primarily used by other Configure units that ask about preprocessor symbols.

cppsymbols

From Cppsym.U:

The variable contains the symbols defined by the C preprocessor alone. The symbols defined by cc or by cc when it calls cpp are not in this list, see ccsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

crypt_r_proto

From d_crypt_r.U:

This variable encodes the prototype of crypt_r. It is zero if d_crypt_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_crypt_r is defined.

cryptlib

From d_crypt.U:

This variable holds -lcrypt or the path to a libcrypt.a archive if the crypt() function is not defined in the standard C library. It is up to the Makefile to use this.

csh

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the csh program. After Configure runs, the value is reset to a plain csh and is not useful.

ctermid_r_proto

From d_ctermid_r.U:

This variable encodes the prototype of ctermid_r. It is zero if d_ctermid_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_ctermid_r is defined.

ctime_r_proto

From d_ctime_r.U:

This variable encodes the prototype of ctime_r. It is zero if d_ctime_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_ctime_r is defined.

d

d_Gconvert

From d_gconvert.U:

This variable holds what Gconvert is defined as to convert floating point numbers into strings. By default, Configure sets this macro to use the first of gconvert, gcvt, or sprintf that pass sprintf-%g-like behavior tests. If perl is using long doubles, the macro uses the first of the following functions that pass Configure's tests: qgcvt, sprintf (if Configure knows how to make sprintf format long doubles--see sPRIgldbl), gconvert, gcvt, and sprintf (casting to double). The gconvert_preference and gconvert_ld_preference variables can be used to alter Configure's preferences, for doubles and long doubles, respectively. If present, they contain a space-separated list of one or more of the above function names in the order they should be tried.

d_Gconvert may be set to override Configure with a platform- specific function. If this function expects a double, a different value may need to be set by the uselongdouble.cbu call-back unit so that long doubles can be formatted without loss of precision.

d_PRIEUldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles. The U in the name is to separate this from d_PRIeldbl so that even case-blind systems can see the difference.

d_PRIFUldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles. The U in the name is to separate this from d_PRIfldbl so that even case-blind systems can see the difference.

d_PRIGUldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles. The U in the name is to separate this from d_PRIgldbl so that even case-blind systems can see the difference.

d_PRIXU64

From quadfio.U:

This variable conditionally defines the PERL_PRIXU64 symbol, which indicates that stdio has a symbol to print 64-bit hExADECimAl numbers. The U in the name is to separate this from d_PRIx64 so that even case-blind systems can see the difference.

d_PRId64

From quadfio.U:

This variable conditionally defines the PERL_PRId64 symbol, which indicates that stdio has a symbol to print 64-bit decimal numbers.

d_PRIeldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles.

d_PRIfldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles.

d_PRIgldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to print long doubles.

d_PRIi64

From quadfio.U:

This variable conditionally defines the PERL_PRIi64 symbol, which indicates that stdio has a symbol to print 64-bit decimal numbers.

d_PRIo64

From quadfio.U:

This variable conditionally defines the PERL_PRIo64 symbol, which indicates that stdio has a symbol to print 64-bit octal numbers.

d_PRIu64

From quadfio.U:

This variable conditionally defines the PERL_PRIu64 symbol, which indicates that stdio has a symbol to print 64-bit unsigned decimal numbers.

d_PRIx64

From quadfio.U:

This variable conditionally defines the PERL_PRIx64 symbol, which indicates that stdio has a symbol to print 64-bit hexadecimal numbers.

d_SCNfldbl

From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indicates that stdio has a symbol to scan long doubles.

d__fwalk

From d__fwalk.U:

This variable conditionally defines HAS__FWALK if _fwalk() is available to apply a function to all the file handles.

d_accept4

From d_accept4.U:

This variable conditionally defines HAS_ACCEPT4 if accept4() is available to accept socket connections.

d_access

From d_access.U:

This variable conditionally defines HAS_ACCESS if the access() system call is available to check for access permissions using real IDs.

d_accessx

From d_accessx.U:

This variable conditionally defines the HAS_ACCESSX symbol, which indicates to the C program that the accessx() routine is available.

d_acosh

From d_acosh.U:

This variable conditionally defines the HAS_ACOSH symbol, which indicates to the C program that the acosh() routine is available.

d_aintl

From d_aintl.U:

This variable conditionally defines the HAS_AINTL symbol, which indicates to the C program that the aintl() routine is available. If copysignl is also present we can emulate modfl.

d_alarm

From d_alarm.U:

This variable conditionally defines the HAS_ALARM symbol, which indicates to the C program that the alarm() routine is available.

d_archlib

From archlib.U:

This variable conditionally defines ARCHLIB to hold the pathname of architecture-dependent library files for $package. If $archlib is the same as $privlib, then this is set to undef.

d_asctime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_ASCTIME64 symbol, which indicates to the C program that the asctime64 () routine is available.

d_asctime_r

From d_asctime_r.U:

This variable conditionally defines the HAS_ASCTIME_R symbol, which indicates to the C program that the asctime_r() routine is available.

d_asinh

From d_asinh.U:

This variable conditionally defines the HAS_ASINH symbol, which indicates to the C program that the asinh() routine is available.

d_atanh

From d_atanh.U:

This variable conditionally defines the HAS_ATANH symbol, which indicates to the C program that the atanh() routine is available.

d_atolf

From atolf.U:

This variable conditionally defines the HAS_ATOLF symbol, which indicates to the C program that the atolf() routine is available.

d_atoll

From atoll.U:

This variable conditionally defines the HAS_ATOLL symbol, which indicates to the C program that the atoll() routine is available.

d_attribute_always_inline

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_ALWAYS_INLINE, which indicates that the C compiler can know that certain functions should always be inlined.

d_attribute_deprecated

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_DEPRECATED, which indicates that GCC can handle the attribute for marking deprecated APIs

d_attribute_format

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_FORMAT, which indicates the C compiler can check for printf-like formats.

d_attribute_malloc

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_MALLOC, which indicates the C compiler can understand functions as having malloc-like semantics.

d_attribute_nonnull

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_NONNULL, which indicates that the C compiler can know that certain arguments must not be NULL, and will check accordingly at compile time.

d_attribute_noreturn

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_NORETURN, which indicates that the C compiler can know that certain functions are guaranteed never to return.

d_attribute_pure

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_PURE, which indicates that the C compiler can know that certain functions are pure functions, meaning that they have no side effects, and only rely on function input and/or global data for their results.

d_attribute_unused

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_UNUSED, which indicates that the C compiler can know that certain variables and arguments may not always be used, and to not throw warnings if they don't get used.

d_attribute_visibility

From d_attribut.U:

This variable conditionally defines the HASATTRIBUTE_VISIBILITY symbol, and indicates different GCC attribute visibility

d_attribute_warn_unused_result

From d_attribut.U:

This variable conditionally defines HASATTRIBUTE_WARN_UNUSED_RESULT, which indicates that the C compiler can know that certain functions have a return values that must not be ignored, such as malloc() or open().

d_backtrace

From d_backtrace.U:

This variable conditionally defines the HAS_BACKTRACE symbol, which indicates to the C program that the backtrace() routine is available to get a stack trace.

d_bsd

From Guess.U:

This symbol conditionally defines the symbol BSD when running on a BSD system.

d_bsdgetpgrp

From d_getpgrp.U:

This variable conditionally defines USE_BSD_GETPGRP if getpgrp needs one arguments whereas USG one needs none.

d_bsdsetpgrp

From d_setpgrp.U:

This variable conditionally defines USE_BSD_SETPGRP if setpgrp needs two arguments whereas USG one needs none. See also d_setpgid for a POSIX interface.

d_builtin_add_overflow

From d_builtin_overflow.U:

This variable conditionally defines HAS_BUILTIN_ADD_OVERFLOW, which indicates that the compiler supports __builtin_add_overflow(x,y,&z) for safely adding x and y into z while checking for overflow.

d_builtin_choose_expr

From d_builtin.U:

This conditionally defines HAS_BUILTIN_CHOOSE_EXPR, which indicates that the compiler supports __builtin_choose_expr(x,y,z). This built-in function is analogous to the x?y:z operator in C, except that the expression returned has its type unaltered by promotion rules. Also, the built-in function does not evaluate the expression that was not chosen.

d_builtin_expect

From d_builtin.U:

This conditionally defines HAS_BUILTIN_EXPECT, which indicates that the compiler supports __builtin_expect(exp,c). You may use __builtin_expect to provide the compiler with branch prediction information.

d_builtin_mul_overflow

From d_builtin_overflow.U:

This variable conditionally defines HAS_BUILTIN_MUL_OVERFLOW, which indicates that the compiler supports __builtin_mul_overflow(x,y,&z) for safely multiplying x and y into z while checking for overflow.

d_builtin_sub_overflow

From d_builtin_overflow.U:

This variable conditionally defines HAS_BUILTIN_SUB_OVERFLOW, which indicates that the compiler supports __builtin_sub_overflow(x,y,&z) for safely subtracting y from x into z while checking for overflow.

d_c99_variadic_macros

From d_c99_variadic.U:

This variable conditionally defines the HAS_C99_VARIADIC_MACROS symbol, which indicates to the C program that C99 variadic macros are available.

d_casti32

From d_casti32.U:

This variable conditionally defines CASTI32, which indicates whether the C compiler can cast large floats to 32-bit ints.

d_castneg

From d_castneg.U:

This variable conditionally defines CASTNEG, which indicates whether the C compiler can cast negative float to unsigned.

d_cbrt

From d_cbrt.U:

This variable conditionally defines the HAS_CBRT symbol, which indicates to the C program that the cbrt() (cube root) function is available.

d_chown

From d_chown.U:

This variable conditionally defines the HAS_CHOWN symbol, which indicates to the C program that the chown() routine is available.

d_chroot

From d_chroot.U:

This variable conditionally defines the HAS_CHROOT symbol, which indicates to the C program that the chroot() routine is available.

d_chsize

From d_chsize.U:

This variable conditionally defines the CHSIZE symbol, which indicates to the C program that the chsize() routine is available to truncate files. You might need a -lx to get this routine.

d_class

From d_class.U:

This variable conditionally defines the HAS_CLASS symbol, which indicates to the C program that the class() routine is available.

d_clearenv

From d_clearenv.U:

This variable conditionally defines the HAS_CLEARENV symbol, which indicates to the C program that the clearenv () routine is available.

d_closedir

From d_closedir.U:

This variable conditionally defines HAS_CLOSEDIR if closedir() is available.

d_cmsghdr_s

From d_cmsghdr_s.U:

This variable conditionally defines the HAS_STRUCT_CMSGHDR symbol, which indicates that the struct cmsghdr is supported.

d_copysign

From d_copysign.U:

This variable conditionally defines the HAS_COPYSIGN symbol, which indicates to the C program that the copysign() routine is available.

d_copysignl

From d_copysignl.U:

This variable conditionally defines the HAS_COPYSIGNL symbol, which indicates to the C program that the copysignl() routine is available. If aintl is also present we can emulate modfl.

d_cplusplus

From d_cplusplus.U:

This variable conditionally defines the USE_CPLUSPLUS symbol, which indicates that a C++ compiler was used to compiled Perl and will be used to compile extensions.

d_crypt

From d_crypt.U:

This variable conditionally defines the CRYPT symbol, which indicates to the C program that the crypt() routine is available to encrypt passwords and the like.

d_crypt_r

From d_crypt_r.U:

This variable conditionally defines the HAS_CRYPT_R symbol, which indicates to the C program that the crypt_r() routine is available.

d_csh

From d_csh.U:

This variable conditionally defines the CSH symbol, which indicates to the C program that the C-shell exists.

d_ctermid

From d_ctermid.U:

This variable conditionally defines CTERMID if ctermid() is available to generate filename for terminal.

d_ctermid_r

From d_ctermid_r.U:

This variable conditionally defines the HAS_CTERMID_R symbol, which indicates to the C program that the ctermid_r() routine is available.

d_ctime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_CTIME64 symbol, which indicates to the C program that the ctime64 () routine is available.

d_ctime_r

From d_ctime_r.U:

This variable conditionally defines the HAS_CTIME_R symbol, which indicates to the C program that the ctime_r() routine is available.

d_cuserid

From d_cuserid.U:

This variable conditionally defines the HAS_CUSERID symbol, which indicates to the C program that the cuserid() routine is available to get character login names.

d_dbminitproto

From d_dbminitproto.U:

This variable conditionally defines the HAS_DBMINIT_PROTO symbol, which indicates to the C program that the system provides a prototype for the dbminit() function. Otherwise, it is up to the program to supply one.

d_difftime

From d_difftime.U:

This variable conditionally defines the HAS_DIFFTIME symbol, which indicates to the C program that the difftime() routine is available.

d_difftime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_DIFFTIME64 symbol, which indicates to the C program that the difftime64 () routine is available.

d_dir_dd_fd

From d_dir_dd_fd.U:

This variable conditionally defines the HAS_DIR_DD_FD symbol, which indicates that the DIR directory stream type contains a member variable called dd_fd.

d_dirfd

From d_dirfd.U:

This variable conditionally defines the HAS_DIRFD constant, which indicates to the C program that dirfd() is available to return the file descriptor of a directory stream.

d_dirnamlen

From i_dirent.U:

This variable conditionally defines DIRNAMLEN, which indicates to the C program that the length of directory entry names is provided by a d_namelen field.

d_dladdr

From d_dladdr.U:

This variable conditionally defines the HAS_DLADDR symbol, which indicates to the C program that the dladdr() routine is available to get a stack trace.

d_dlerror

From d_dlerror.U:

This variable conditionally defines the HAS_DLERROR symbol, which indicates to the C program that the dlerror() routine is available.

d_dlopen

From d_dlopen.U:

This variable conditionally defines the HAS_DLOPEN symbol, which indicates to the C program that the dlopen() routine is available.

d_dlsymun

From d_dlsymun.U:

This variable conditionally defines DLSYM_NEEDS_UNDERSCORE, which indicates that we need to prepend an underscore to the symbol name before calling dlsym().

d_dosuid

From d_dosuid.U:

This variable conditionally defines the symbol DOSUID, which tells the C program that it should insert setuid emulation code on hosts which have setuid #! scripts disabled.

d_double_has_inf

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_HAS_INF which indicates that the double type has an infinity.

d_double_has_nan

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_HAS_NAN which indicates that the double type has a not-a-number.

d_double_has_negative_zero

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_HAS_NEGATIVE_ZERO which indicates that the double type has a negative zero.

d_double_has_subnormals

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_HAS_SUBNORMALS which indicates that the double type has subnormals (denormals).

d_double_style_cray

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_STYLE_CRAY which indicates that the double is the 64-bit CRAY mainframe format.

d_double_style_ibm

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_STYLE_IBM, which indicates that the double is the 64-bit IBM mainframe format.

d_double_style_ieee

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_STYLE_IEEE, which indicates that the double is the 64-bit IEEE 754.

d_double_style_vax

From longdblfio.U:

This variable conditionally defines the symbol DOUBLE_STYLE_VAX, which indicates that the double is the 64-bit VAX format D or G.

d_drand48_r

From d_drand48_r.U:

This variable conditionally defines the HAS_DRAND48_R symbol, which indicates to the C program that the drand48_r() routine is available.

d_drand48proto

From d_drand48proto.U:

This variable conditionally defines the HAS_DRAND48_PROTO symbol, which indicates to the C program that the system provides a prototype for the drand48() function. Otherwise, it is up to the program to supply one.

d_dup2

From d_dup2.U:

This variable conditionally defines HAS_DUP2 if dup2() is available to duplicate file descriptors.

d_dup3

From d_dup3.U:

This variable conditionally defines HAS_DUP3 if dup3() is available to duplicate file descriptors.

d_duplocale

From d_newlocale.U:

This variable conditionally defines the HAS_DUPLOCALE symbol, which indicates to the C program that the duplocale() routine is available to duplicate a locale object.

d_eaccess

From d_eaccess.U:

This variable conditionally defines the HAS_EACCESS symbol, which indicates to the C program that the eaccess() routine is available.

d_endgrent

From d_endgrent.U:

This variable conditionally defines the HAS_ENDGRENT symbol, which indicates to the C program that the endgrent() routine is available for sequential access of the group database.

d_endgrent_r

From d_endgrent_r.U:

This variable conditionally defines the HAS_ENDGRENT_R symbol, which indicates to the C program that the endgrent_r() routine is available.

d_endhent

From d_endhent.U:

This variable conditionally defines HAS_ENDHOSTENT if endhostent() is available to close whatever was being used for host queries.

d_endhostent_r

From d_endhostent_r.U:

This variable conditionally defines the HAS_ENDHOSTENT_R symbol, which indicates to the C program that the endhostent_r() routine is available.

d_endnent

From d_endnent.U:

This variable conditionally defines HAS_ENDNETENT if endnetent() is available to close whatever was being used for network queries.

d_endnetent_r

From d_endnetent_r.U:

This variable conditionally defines the HAS_ENDNETENT_R symbol, which indicates to the C program that the endnetent_r() routine is available.

d_endpent

From d_endpent.U:

This variable conditionally defines HAS_ENDPROTOENT if endprotoent() is available to close whatever was being used for protocol queries.

d_endprotoent_r

From d_endprotoent_r.U:

This variable conditionally defines the HAS_ENDPROTOENT_R symbol, which indicates to the C program that the endprotoent_r() routine is available.

d_endpwent

From d_endpwent.U:

This variable conditionally defines the HAS_ENDPWENT symbol, which indicates to the C program that the endpwent() routine is available for sequential access of the passwd database.

d_endpwent_r

From d_endpwent_r.U:

This variable conditionally defines the HAS_ENDPWENT_R symbol, which indicates to the C program that the endpwent_r() routine is available.

d_endsent

From d_endsent.U:

This variable conditionally defines HAS_ENDSERVENT if endservent() is available to close whatever was being used for service queries.

d_endservent_r

From d_endservent_r.U:

This variable conditionally defines the HAS_ENDSERVENT_R symbol, which indicates to the C program that the endservent_r() routine is available.

d_eofnblk

From nblock_io.U:

This variable conditionally defines EOF_NONBLOCK if EOF can be seen when reading from a non-blocking I/O source.

d_erf

From d_erf.U:

This variable conditionally defines the HAS_ERF symbol, which indicates to the C program that the erf() routine is available.

d_erfc

From d_erfc.U:

This variable conditionally defines the HAS_ERFC symbol, which indicates to the C program that the erfc() routine is available.

d_eunice

From Guess.U:

This variable conditionally defines the symbols EUNICE and VAX, which alerts the C program that it must deal with idiosyncrasies of VMS.

d_exp2

From d_exp2.U:

This variable conditionally defines the HAS_EXP2 symbol, which indicates to the C program that the exp2() routine is available.

d_expm1

From d_expm1.U:

This variable conditionally defines the HAS_EXPM1 symbol, which indicates to the C program that the expm1() routine is available.

d_faststdio

From d_faststdio.U:

This variable conditionally defines the HAS_FAST_STDIO symbol, which indicates to the C program that the "fast stdio" is available to manipulate the stdio buffers directly.

d_fchdir

From d_fchdir.U:

This variable conditionally defines the HAS_FCHDIR symbol, which indicates to the C program that the fchdir() routine is available.

d_fchmod

From d_fchmod.U:

This variable conditionally defines the HAS_FCHMOD symbol, which indicates to the C program that the fchmod() routine is available to change mode of opened files.

d_fchmodat

From d_fsat.U:

This variable conditionally defines the HAS_FCHMODAT symbol, which indicates the POSIX fchmodat() function is available.

d_fchown

From d_fchown.U:

This variable conditionally defines the HAS_FCHOWN symbol, which indicates to the C program that the fchown() routine is available to change ownership of opened files.

d_fcntl

From d_fcntl.U:

This variable conditionally defines the HAS_FCNTL symbol, and indicates whether the fcntl() function exists

d_fcntl_can_lock

From d_fcntl_can_lock.U:

This variable conditionally defines the FCNTL_CAN_LOCK symbol and indicates whether file locking with fcntl() works.

d_fd_macros

From d_fd_set.U:

This variable contains the eventual value of the HAS_FD_MACROS symbol, which indicates if your C compiler knows about the macros which manipulate an fd_set.

d_fd_set

From d_fd_set.U:

This variable contains the eventual value of the HAS_FD_SET symbol, which indicates if your C compiler knows about the fd_set typedef.

d_fdclose

From d_fdclose.U:

This variable conditionally defines the HAS_FDCLOSE symbol, which indicates to the C program that the fdclose() routine is available.

d_fdim

From d_fdim.U:

This variable conditionally defines the HAS_FDIM symbol, which indicates to the C program that the fdim() routine is available.

d_fds_bits

From d_fd_set.U:

This variable contains the eventual value of the HAS_FDS_BITS symbol, which indicates if your fd_set typedef contains the fds_bits member. If you have an fd_set typedef, but the dweebs who installed it did a half-fast job and neglected to provide the macros to manipulate an fd_set, HAS_FDS_BITS will let us know how to fix the gaffe.

d_fegetround

From d_fegetround.U:

This variable conditionally defines HAS_FEGETROUND if fegetround() is available to get the floating point rounding mode.

d_ffs

From d_ffs.U:

This variable conditionally defines the HAS_FFS symbol, which indicates to the C program that the ffs() routine is available to find the first bit which is set in its integer argument.

d_ffsl

From d_ffs.U:

This variable conditionally defines the HAS_FFSL symbol, which indicates to the C program that the ffsl() routine is available to find the first bit which is set in its long integer argument.

d_fgetpos

From d_fgetpos.U:

This variable conditionally defines HAS_FGETPOS if fgetpos() is available to get the file position indicator.

d_finite

From d_finite.U:

This variable conditionally defines the HAS_FINITE symbol, which indicates to the C program that the finite() routine is available.

d_finitel

From d_finitel.U:

This variable conditionally defines the HAS_FINITEL symbol, which indicates to the C program that the finitel() routine is available.

d_flexfnam

From d_flexfnam.U:

This variable conditionally defines the FLEXFILENAMES symbol, which indicates that the system supports filenames longer than 14 characters.

d_flock

From d_flock.U:

This variable conditionally defines HAS_FLOCK if flock() is available to do file locking.

d_flockproto

From d_flockproto.U:

This variable conditionally defines the HAS_FLOCK_PROTO symbol, which indicates to the C program that the system provides a prototype for the flock() function. Otherwise, it is up to the program to supply one.

d_fma

From d_fma.U:

This variable conditionally defines the HAS_FMA symbol, which indicates to the C program that the fma() routine is available.

d_fmax

From d_fmax.U:

This variable conditionally defines the HAS_FMAX symbol, which indicates to the C program that the fmax() routine is available.

d_fmin

From d_fmin.U:

This variable conditionally defines the HAS_FMIN symbol, which indicates to the C program that the fmin() routine is available.

d_fork

From d_fork.U:

This variable conditionally defines the HAS_FORK symbol, which indicates to the C program that the fork() routine is available.

d_fp_class

From d_fp_class.U:

This variable conditionally defines the HAS_FP_CLASS symbol, which indicates to the C program that the fp_class() routine is available.

d_fp_classify

From d_fpclassify.U:

This variable conditionally defines the HAS_FP_CLASSIFY symbol, which indicates to the C program that the fp_classify() routine is available.

d_fp_classl

From d_fp_classl.U:

This variable conditionally defines the HAS_FP_CLASSL symbol, which indicates to the C program that the fp_classl() routine is available.

d_fpathconf

From d_pathconf.U:

This variable conditionally defines the HAS_FPATHCONF symbol, which indicates to the C program that the pathconf() routine is available to determine file-system related limits and options associated with a given open file descriptor.

d_fpclass

From d_fpclass.U:

This variable conditionally defines the HAS_FPCLASS symbol, which indicates to the C program that the fpclass() routine is available.

d_fpclassify

From d_fpclassify.U:

This variable conditionally defines the HAS_FPCLASSIFY symbol, which indicates to the C program that the fpclassify() routine is available.

d_fpclassl

From d_fpclassl.U:

This variable conditionally defines the HAS_FPCLASSL symbol, which indicates to the C program that the fpclassl() routine is available.

d_fpgetround

From d_fpgetround.U:

This variable conditionally defines HAS_FPGETROUND if fpgetround() is available to get the floating point rounding mode.

d_fpos64_t

From d_fpos64_t.U:

This symbol will be defined if the C compiler supports fpos64_t.

d_freelocale

From d_newlocale.U:

This variable conditionally defines the HAS_FREELOCALE symbol, which indicates to the C program that the freelocale() routine is available to deallocates the resources associated with a locale object.

d_frexpl

From d_frexpl.U:

This variable conditionally defines the HAS_FREXPL symbol, which indicates to the C program that the frexpl() routine is available.

d_fs_data_s

From d_fs_data_s.U:

This variable conditionally defines the HAS_STRUCT_FS_DATA symbol, which indicates that the struct fs_data is supported.

d_fseeko

From d_fseeko.U:

This variable conditionally defines the HAS_FSEEKO symbol, which indicates to the C program that the fseeko() routine is available.

d_fsetpos

From d_fsetpos.U:

This variable conditionally defines HAS_FSETPOS if fsetpos() is available to set the file position indicator.

d_fstatfs

From d_fstatfs.U:

This variable conditionally defines the HAS_FSTATFS symbol, which indicates to the C program that the fstatfs() routine is available.

d_fstatvfs

From d_statvfs.U:

This variable conditionally defines the HAS_FSTATVFS symbol, which indicates to the C program that the fstatvfs() routine is available.

d_fsync

From d_fsync.U:

This variable conditionally defines the HAS_FSYNC symbol, which indicates to the C program that the fsync() routine is available.

d_ftello

From d_ftello.U:

This variable conditionally defines the HAS_FTELLO symbol, which indicates to the C program that the ftello() routine is available.

d_ftime

From d_ftime.U:

This variable conditionally defines the HAS_FTIME symbol, which indicates that the ftime() routine exists. The ftime() routine is basically a sub-second accuracy clock.

d_futimes

From d_futimes.U:

This variable conditionally defines the HAS_FUTIMES symbol, which indicates to the C program that the futimes() routine is available.

d_gai_strerror

From d_gai_strerror.U:

This variable conditionally defines the HAS_GAI_STRERROR symbol if the gai_strerror() routine is available and can be used to translate error codes returned by getaddrinfo() into human readable strings.

d_gdbm_ndbm_h_uses_prototypes

From i_ndbm.U:

This variable conditionally defines the NDBM_H_USES_PROTOTYPES symbol, which indicates that the gdbm-ndbm.h include file uses real ANSI C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_gdbmndbm_h_uses_prototypes

From i_ndbm.U:

This variable conditionally defines the NDBM_H_USES_PROTOTYPES symbol, which indicates that the gdbm/ndbm.h include file uses real ANSI C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_getaddrinfo

From d_getaddrinfo.U:

This variable conditionally defines the HAS_GETADDRINFO symbol, which indicates to the C program that the getaddrinfo() function is available.

d_getcwd

From d_getcwd.U:

This variable conditionally defines the HAS_GETCWD symbol, which indicates to the C program that the getcwd() routine is available to get the current working directory.

d_getenv_preserves_other_thread

From d_getenv_thread.U:

This variable conditionally defines the GETENV_PRESERVES_OTHER_THREAD symbol, which indicates to the C program that the getenv() system call does not zap the static buffer in a different thread.

d_getespwnam

From d_getespwnam.U:

This variable conditionally defines HAS_GETESPWNAM if getespwnam() is available to retrieve enhanced (shadow) password entries by name.

d_getfsstat

From d_getfsstat.U:

This variable conditionally defines the HAS_GETFSSTAT symbol, which indicates to the C program that the getfsstat() routine is available.

d_getgrent

From d_getgrent.U:

This variable conditionally defines the HAS_GETGRENT symbol, which indicates to the C program that the getgrent() routine is available for sequential access of the group database.

d_getgrent_r

From d_getgrent_r.U:

This variable conditionally defines the HAS_GETGRENT_R symbol, which indicates to the C program that the getgrent_r() routine is available.

d_getgrgid_r

From d_getgrgid_r.U:

This variable conditionally defines the HAS_GETGRGID_R symbol, which indicates to the C program that the getgrgid_r() routine is available.

d_getgrnam_r

From d_getgrnam_r.U:

This variable conditionally defines the HAS_GETGRNAM_R symbol, which indicates to the C program that the getgrnam_r() routine is available.

d_getgrps

From d_getgrps.U:

This variable conditionally defines the HAS_GETGROUPS symbol, which indicates to the C program that the getgroups() routine is available to get the list of process groups.

d_gethbyaddr

From d_gethbyad.U:

This variable conditionally defines the HAS_GETHOSTBYADDR symbol, which indicates to the C program that the gethostbyaddr() routine is available to look up hosts by their IP addresses.

d_gethbyname

From d_gethbynm.U:

This variable conditionally defines the HAS_GETHOSTBYNAME symbol, which indicates to the C program that the gethostbyname() routine is available to look up host names in some data base or other.

d_gethent

From d_gethent.U:

This variable conditionally defines HAS_GETHOSTENT if gethostent() is available to look up host names in some data base or another.

d_gethname

From d_gethname.U:

This variable conditionally defines the HAS_GETHOSTNAME symbol, which indicates to the C program that the gethostname() routine may be used to derive the host name.

d_gethostbyaddr_r

From d_gethostbyaddr_r.U:

This variable conditionally defines the HAS_GETHOSTBYADDR_R symbol, which indicates to the C program that the gethostbyaddr_r() routine is available.

d_gethostbyname_r

From d_gethostbyname_r.U:

This variable conditionally defines the HAS_GETHOSTBYNAME_R symbol, which indicates to the C program that the gethostbyname_r() routine is available.

d_gethostent_r

From d_gethostent_r.U:

This variable conditionally defines the HAS_GETHOSTENT_R symbol, which indicates to the C program that the gethostent_r() routine is available.

d_gethostprotos

From d_gethostprotos.U:

This variable conditionally defines the HAS_GETHOST_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various gethost*() functions. See also netdbtype.U for probing for various netdb types.

d_getitimer

From d_getitimer.U:

This variable conditionally defines the HAS_GETITIMER symbol, which indicates to the C program that the getitimer() routine is available.

d_getlogin

From d_getlogin.U:

This variable conditionally defines the HAS_GETLOGIN symbol, which indicates to the C program that the getlogin() routine is available to get the login name.

d_getlogin_r

From d_getlogin_r.U:

This variable conditionally defines the HAS_GETLOGIN_R symbol, which indicates to the C program that the getlogin_r() routine is available.

d_getmnt

From d_getmnt.U:

This variable conditionally defines the HAS_GETMNT symbol, which indicates to the C program that the getmnt() routine is available to retrieve one or more mount info blocks by filename.

d_getmntent

From d_getmntent.U:

This variable conditionally defines the HAS_GETMNTENT symbol, which indicates to the C program that the getmntent() routine is available to iterate through mounted files to get their mount info.

d_getnameinfo

From d_getnameinfo.U:

This variable conditionally defines the HAS_GETNAMEINFO symbol, which indicates to the C program that the getnameinfo() function is available.

d_getnbyaddr

From d_getnbyad.U:

This variable conditionally defines the HAS_GETNETBYADDR symbol, which indicates to the C program that the getnetbyaddr() routine is available to look up networks by their IP addresses.

d_getnbyname

From d_getnbynm.U:

This variable conditionally defines the HAS_GETNETBYNAME symbol, which indicates to the C program that the getnetbyname() routine is available to look up networks by their names.

d_getnent

From d_getnent.U:

This variable conditionally defines HAS_GETNETENT if getnetent() is available to look up network names in some data base or another.

d_getnetbyaddr_r

From d_getnetbyaddr_r.U:

This variable conditionally defines the HAS_GETNETBYADDR_R symbol, which indicates to the C program that the getnetbyaddr_r() routine is available.

d_getnetbyname_r

From d_getnetbyname_r.U:

This variable conditionally defines the HAS_GETNETBYNAME_R symbol, which indicates to the C program that the getnetbyname_r() routine is available.

d_getnetent_r

From d_getnetent_r.U:

This variable conditionally defines the HAS_GETNETENT_R symbol, which indicates to the C program that the getnetent_r() routine is available.

d_getnetprotos

From d_getnetprotos.U:

This variable conditionally defines the HAS_GETNET_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getnet*() functions. See also netdbtype.U for probing for various netdb types.

d_getpagsz

From d_getpagsz.U:

This variable conditionally defines HAS_GETPAGESIZE if getpagesize() is available to get the system page size.

d_getpbyname

From d_getprotby.U:

This variable conditionally defines the HAS_GETPROTOBYNAME symbol, which indicates to the C program that the getprotobyname() routine is available to look up protocols by their name.

d_getpbynumber

From d_getprotby.U:

This variable conditionally defines the HAS_GETPROTOBYNUMBER symbol, which indicates to the C program that the getprotobynumber() routine is available to look up protocols by their number.

d_getpent

From d_getpent.U:

This variable conditionally defines HAS_GETPROTOENT if getprotoent() is available to look up protocols in some data base or another.

d_getpgid

From d_getpgid.U:

This variable conditionally defines the HAS_GETPGID symbol, which indicates to the C program that the getpgid(pid) function is available to get the process group id.

d_getpgrp

From d_getpgrp.U:

This variable conditionally defines HAS_GETPGRP if getpgrp() is available to get the current process group.

d_getpgrp2

From d_getpgrp2.U:

This variable conditionally defines the HAS_GETPGRP2 symbol, which indicates to the C program that the getpgrp2() (as in DG/UX) routine is available to get the current process group.

d_getppid

From d_getppid.U:

This variable conditionally defines the HAS_GETPPID symbol, which indicates to the C program that the getppid() routine is available to get the parent process ID.

d_getprior

From d_getprior.U:

This variable conditionally defines HAS_GETPRIORITY if getpriority() is available to get a process's priority.

d_getprotobyname_r

From d_getprotobyname_r.U:

This variable conditionally defines the HAS_GETPROTOBYNAME_R symbol, which indicates to the C program that the getprotobyname_r() routine is available.

d_getprotobynumber_r

From d_getprotobynumber_r.U:

This variable conditionally defines the HAS_GETPROTOBYNUMBER_R symbol, which indicates to the C program that the getprotobynumber_r() routine is available.

d_getprotoent_r

From d_getprotoent_r.U:

This variable conditionally defines the HAS_GETPROTOENT_R symbol, which indicates to the C program that the getprotoent_r() routine is available.

d_getprotoprotos

From d_getprotoprotos.U:

This variable conditionally defines the HAS_GETPROTO_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getproto*() functions. See also netdbtype.U for probing for various netdb types.

d_getprpwnam

From d_getprpwnam.U:

This variable conditionally defines HAS_GETPRPWNAM if getprpwnam() is available to retrieve protected (shadow) password entries by name.

d_getpwent

From d_getpwent.U:

This variable conditionally defines the HAS_GETPWENT symbol, which indicates to the C program that the getpwent() routine is available for sequential access of the passwd database.

d_getpwent_r

From d_getpwent_r.U:

This variable conditionally defines the HAS_GETPWENT_R symbol, which indicates to the C program that the getpwent_r() routine is available.

d_getpwnam_r

From d_getpwnam_r.U:

This variable conditionally defines the HAS_GETPWNAM_R symbol, which indicates to the C program that the getpwnam_r() routine is available.

d_getpwuid_r

From d_getpwuid_r.U:

This variable conditionally defines the HAS_GETPWUID_R symbol, which indicates to the C program that the getpwuid_r() routine is available.

d_getsbyname

From d_getsrvby.U:

This variable conditionally defines the HAS_GETSERVBYNAME symbol, which indicates to the C program that the getservbyname() routine is available to look up services by their name.

d_getsbyport

From d_getsrvby.U:

This variable conditionally defines the HAS_GETSERVBYPORT symbol, which indicates to the C program that the getservbyport() routine is available to look up services by their port.

d_getsent

From d_getsent.U:

This variable conditionally defines HAS_GETSERVENT if getservent() is available to look up network services in some data base or another.

d_getservbyname_r

From d_getservbyname_r.U:

This variable conditionally defines the HAS_GETSERVBYNAME_R symbol, which indicates to the C program that the getservbyname_r() routine is available.

d_getservbyport_r

From d_getservbyport_r.U:

This variable conditionally defines the HAS_GETSERVBYPORT_R symbol, which indicates to the C program that the getservbyport_r() routine is available.

d_getservent_r

From d_getservent_r.U:

This variable conditionally defines the HAS_GETSERVENT_R symbol, which indicates to the C program that the getservent_r() routine is available.

d_getservprotos

From d_getservprotos.U:

This variable conditionally defines the HAS_GETSERV_PROTOS symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getserv*() functions. See also netdbtype.U for probing for various netdb types.

d_getspnam

From d_getspnam.U:

This variable conditionally defines HAS_GETSPNAM if getspnam() is available to retrieve SysV shadow password entries by name.

d_getspnam_r

From d_getspnam_r.U:

This variable conditionally defines the HAS_GETSPNAM_R symbol, which indicates to the C program that the getspnam_r() routine is available.

d_gettimeod

From d_ftime.U:

This variable conditionally defines the HAS_GETTIMEOFDAY symbol, which indicates that the gettimeofday() system call exists (to obtain a sub-second accuracy clock). You should probably include <sys/resource.h>.

d_gmtime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_GMTIME64 symbol, which indicates to the C program that the gmtime64 () routine is available.

d_gmtime_r

From d_gmtime_r.U:

This variable conditionally defines the HAS_GMTIME_R symbol, which indicates to the C program that the gmtime_r() routine is available.

d_gnulibc

From d_gnulibc.U:

Defined if we're dealing with the GNU C Library.

d_grpasswd

From i_grp.U:

This variable conditionally defines GRPASSWD, which indicates that struct group in <grp.h> contains gr_passwd.

d_has_C_UTF8

From d_setlocale.U:

This variable is set to either true or false depending on whether the compilation system supports the C.UTF-8 locale.

d_hasmntopt

From d_hasmntopt.U:

This variable conditionally defines the HAS_HASMNTOPT symbol, which indicates to the C program that the hasmntopt() routine is available to query the mount options of file systems.

d_htonl

From d_htonl.U:

This variable conditionally defines HAS_HTONL if htonl() and its friends are available to do network order byte swapping.

d_hypot

From d_hypot.U:

This variable conditionally defines HAS_HYPOT if hypot is available for numerically stable hypotenuse function.

d_ilogb

From d_ilogb.U:

This variable conditionally defines the HAS_ILOGB symbol, which indicates to the C program that the ilogb() routine is available for extracting the exponent of double x as a signed integer.

d_ilogbl

From d_ilogbl.U:

This variable conditionally defines the HAS_ILOGBL symbol, which indicates to the C program that the ilogbl() routine is available for extracting the exponent of long double x as a signed integer. If scalbnl is also present we can emulate frexpl.

d_inc_version_list

From inc_version_list.U:

This variable conditionally defines PERL_INC_VERSION_LIST. It is set to undef when PERL_INC_VERSION_LIST is empty.

d_inetaton

From d_inetaton.U:

This variable conditionally defines the HAS_INET_ATON symbol, which indicates to the C program that the inet_aton() function is available to parse IP address dotted-quad strings.

d_inetntop

From d_inetntop.U:

This variable conditionally defines the HAS_INETNTOP symbol, which indicates to the C program that the inet_ntop() function is available.

d_inetpton

From d_inetpton.U:

This variable conditionally defines the HAS_INETPTON symbol, which indicates to the C program that the inet_pton() function is available.

d_int64_t

From d_int64_t.U:

This symbol will be defined if the C compiler supports int64_t.

d_ip_mreq

From d_socket.U:

This variable conditionally defines the HAS_IP_MREQ symbol, which indicates the availability of a struct ip_mreq.

d_ip_mreq_source

From d_socket.U:

This variable conditionally defines the HAS_IP_MREQ_SOURCE symbol, which indicates the availability of a struct ip_mreq_source.

d_ipv6_mreq

From d_socket.U:

This variable conditionally defines the HAS_IPV6_MREQ symbol, which indicates the availability of a struct ipv6_mreq.

d_ipv6_mreq_source

From d_socket.U:

This variable conditionally defines the HAS_IPV6_MREQ_SOURCE symbol, which indicates the availability of a struct ipv6_mreq_source.

d_isascii

From d_isascii.U:

This variable conditionally defines the HAS_ISASCII constant, which indicates to the C program that isascii() is available.

d_isblank

From d_isblank.U:

This variable conditionally defines the HAS_ISBLANK constant, which indicates to the C program that isblank() is available.

d_isfinite

From d_isfinite.U:

This variable conditionally defines the HAS_ISFINITE symbol, which indicates to the C program that the isfinite() routine is available.

d_isfinitel

From d_isfinitel.U:

This variable conditionally defines the HAS_ISFINITEL symbol, which indicates to the C program that the isfinitel() routine is available.

d_isinf

From d_isinf.U:

This variable conditionally defines the HAS_ISINF symbol, which indicates to the C program that the isinf() routine is available.

d_isinfl

From d_isinfl.U:

This variable conditionally defines the HAS_ISINFL symbol, which indicates to the C program that the isinfl() routine is available.

d_isless

From d_isless.U:

This variable conditionally defines the HAS_ISLESS symbol, which indicates to the C program that the isless() routine is available.

d_isnan

From d_isnan.U:

This variable conditionally defines the HAS_ISNAN symbol, which indicates to the C program that the isnan() routine is available.

d_isnanl

From d_isnanl.U:

This variable conditionally defines the HAS_ISNANL symbol, which indicates to the C program that the isnanl() routine is available.

d_isnormal

From d_isnormal.U:

This variable conditionally defines the HAS_ISNORMAL symbol, which indicates to the C program that the isnormal() routine is available.

d_j0

From d_j0.U:

This variable conditionally defines the HAS_J0 symbol, which indicates to the C program that the j0() routine is available.

d_j0l

From d_j0.U:

This variable conditionally defines the HAS_J0L symbol, which indicates to the C program that the j0l() routine is available.

d_killpg

From d_killpg.U:

This variable conditionally defines the HAS_KILLPG symbol, which indicates to the C program that the killpg() routine is available to kill process groups.

d_lc_monetary_2008

From d_lc_monetary_2008.U:

This variable conditionally defines HAS_LC_MONETARY_2008 if libc has the international currency locale rules from POSIX 1003.1-2008.

d_lchown

From d_lchown.U:

This variable conditionally defines the HAS_LCHOWN symbol, which indicates to the C program that the lchown() routine is available to operate on a symbolic link (instead of following the link).

d_ldbl_dig

From d_ldbl_dig.U:

This variable conditionally defines d_ldbl_dig if this system's header files provide LDBL_DIG, which is the number of significant digits in a long double precision number.

d_ldexpl

From d_longdbl.U:

This variable conditionally defines the HAS_LDEXPL symbol, which indicates to the C program that the ldexpl() routine is available.

d_lgamma

From d_lgamma.U:

This variable conditionally defines the HAS_LGAMMA symbol, which indicates to the C program that the lgamma() routine is available for the log gamma function. See also d_tgamma and d_lgamma_r.

d_lgamma_r

From d_lgamma_r.U:

This variable conditionally defines the HAS_LGAMMA_R symbol, which indicates to the C program that the lgamma_r() routine is available for the log gamma function, without using the global signgam variable.

d_libm_lib_version

From d_libm_lib_version.U:

This variable conditionally defines the LIBM_LIB_VERSION symbol, which indicates to the C program that math.h defines _LIB_VERSION being available in libm

d_libname_unique

From so.U:

This variable is defined if the target system insists on unique basenames for shared library files. This is currently true on Android, false everywhere else we know of. Defaults to undef.

From d_link.U:

This variable conditionally defines HAS_LINK if link() is available to create hard links.

d_linkat

From d_fsat.U:

This variable conditionally defines the HAS_LINKAT symbol, which indicates the POSIX linkat() function is available.

d_llrint

From d_llrint.U:

This variable conditionally defines the HAS_LLRINT symbol, which indicates to the C program that the llrint() routine is available to return the long long value closest to a double (according to the current rounding mode).

d_llrintl

From d_llrintl.U:

This variable conditionally defines the HAS_LLRINTL symbol, which indicates to the C program that the llrintl() routine is available to return the long long value closest to a long double (according to the current rounding mode).

d_llround

From d_llround.U:

This variable conditionally defines the HAS_LLROUND symbol, which indicates to the C program that the llround() routine is available to return the long long value nearest to x.

d_llroundl

From d_llroundl.U:

This variable conditionally defines the HAS_LLROUNDL symbol, which indicates to the C program that the llroundl() routine is available to return the long long value nearest to x away from zero.

d_localeconv_l

From d_localeconv_l.U:

This variable conditionally defines the HAS_LOCALECONV_L symbol, which indicates to the C program that the localeconv_l() routine is available.

d_localtime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_LOCALTIME64 symbol, which indicates to the C program that the localtime64 () routine is available.

d_localtime_r

From d_localtime_r.U:

This variable conditionally defines the HAS_LOCALTIME_R symbol, which indicates to the C program that the localtime_r() routine is available.

d_localtime_r_needs_tzset

From d_localtime_r.U:

This variable conditionally defines the LOCALTIME_R_NEEDS_TZSET symbol, which makes us call tzset before localtime_r()

d_locconv

From d_locconv.U:

This variable conditionally defines HAS_LOCALECONV if localeconv() is available for numeric and monetary formatting conventions.

d_lockf

From d_lockf.U:

This variable conditionally defines HAS_LOCKF if lockf() is available to do file locking.

d_log1p

From d_log1p.U:

This variable conditionally defines the HAS_LOG1P symbol, which indicates to the C program that the logp1() routine is available to compute log(1 + x) for values of x close to zero.

d_log2

From d_log2.U:

This variable conditionally defines the HAS_LOG2 symbol, which indicates to the C program that the log2() routine is available to compute log base two.

d_logb

From d_logb.U:

This variable conditionally defines the HAS_LOGB symbol, which indicates to the C program that the logb() routine is available to extract the exponent of x.

d_long_double_style_ieee

From d_longdbl.U:

This variable conditionally defines LONG_DOUBLE_STYLE_IEEE if the long double is any of the IEEE 754 style long doubles: LONG_DOUBLE_STYLE_IEEE_STD, LONG_DOUBLE_STYLE_IEEE_EXTENDED, LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE.

d_long_double_style_ieee_doubledouble

From d_longdbl.U:

This variable conditionally defines LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE if the long double is the 128-bit IEEE 754 double-double.

d_long_double_style_ieee_extended

From d_longdbl.U:

This variable conditionally defines LONG_DOUBLE_STYLE_IEEE_EXTENDED if the long double is the 80-bit IEEE 754 extended precision. Note that despite the extended this is less than the std, since this is an extension of the double precision.

d_long_double_style_ieee_std

From d_longdbl.U:

This variable conditionally defines LONG_DOUBLE_STYLE_IEEE_STD if the long double is the 128-bit IEEE 754.

d_long_double_style_vax

From d_longdbl.U:

This variable conditionally defines LONG_DOUBLE_STYLE_VAX if the long double is the 128-bit VAX format H.

d_longdbl

From d_longdbl.U:

This variable conditionally defines HAS_LONG_DOUBLE if the long double type is supported.

d_longlong

From d_longlong.U:

This variable conditionally defines HAS_LONG_LONG if the long long type is supported.

d_lrint

From d_lrint.U:

This variable conditionally defines the HAS_LRINT symbol, which indicates to the C program that the lrint() routine is available to return the integral value closest to a double (according to the current rounding mode).

d_lrintl

From d_lrintl.U:

This variable conditionally defines the HAS_LRINTL symbol, which indicates to the C program that the lrintl() routine is available to return the integral value closest to a long double (according to the current rounding mode).

d_lround

From d_lround.U:

This variable conditionally defines the HAS_LROUND symbol, which indicates to the C program that the lround() routine is available to return the integral value nearest to x.

d_lroundl

From d_lroundl.U:

This variable conditionally defines the HAS_LROUNDL symbol, which indicates to the C program that the lroundl() routine is available to return the integral value nearest to x away from zero.

d_lseekproto

From d_lseekproto.U:

This variable conditionally defines the HAS_LSEEK_PROTO symbol, which indicates to the C program that the system provides a prototype for the lseek() function. Otherwise, it is up to the program to supply one.

d_lstat

From d_lstat.U:

This variable conditionally defines HAS_LSTAT if lstat() is available to do file stats on symbolic links.

d_madvise

From d_madvise.U:

This variable conditionally defines HAS_MADVISE if madvise() is available to map a file into memory.

d_malloc_good_size

From d_malloc_size.U:

This symbol, if defined, indicates that the malloc_good_size routine is available for use.

d_malloc_size

From d_malloc_size.U:

This symbol, if defined, indicates that the malloc_size routine is available for use.

d_malloc_usable_size

From d_malloc_size.U:

This symbol, if defined, indicates that the malloc_usable_size routine is available for use.

d_mblen

From d_mblen.U:

This variable conditionally defines the HAS_MBLEN symbol, which indicates to the C program that the mblen() routine is available to find the number of bytes in a multibyte character.

d_mbrlen

From d_mbrlen.U:

This variable conditionally defines the HAS_MBRLEN symbol if the mbrlen() routine is available to be used to get the length of multi-byte character strings.

d_mbrtowc

From d_mbrtowc.U:

This variable conditionally defines the HAS_MBRTOWC symbol if the mbrtowc() routine is available to be used to convert a multi-byte character into a wide character.

d_mbstowcs

From d_mbstowcs.U:

This variable conditionally defines the HAS_MBSTOWCS symbol, which indicates to the C program that the mbstowcs() routine is available to convert a multibyte string into a wide character string.

d_mbtowc

From d_mbtowc.U:

This variable conditionally defines the HAS_MBTOWC symbol, which indicates to the C program that the mbtowc() routine is available to convert multibyte to a wide character.

d_memmem

From d_memmem.U:

This variable conditionally defines the HAS_MEMMEM symbol, which indicates to the C program that the memmem() routine is available to return a pointer to the start of the first occurrence of a substring in a memory area (or NULL if not found).

d_memrchr

From d_memrchr.U:

This variable conditionally defines the HAS_MEMRCHR symbol, which indicates to the C program that the memrchr() routine is available to return a pointer to the last occurrence of a byte in a memory area (or NULL if not found).

d_mkdir

From d_mkdir.U:

This variable conditionally defines the HAS_MKDIR symbol, which indicates to the C program that the mkdir() routine is available to create directories..

d_mkdtemp

From d_mkdtemp.U:

This variable conditionally defines the HAS_MKDTEMP symbol, which indicates to the C program that the mkdtemp() routine is available to exclusively create a uniquely named temporary directory.

d_mkfifo

From d_mkfifo.U:

This variable conditionally defines the HAS_MKFIFO symbol, which indicates to the C program that the mkfifo() routine is available.

d_mkostemp

From d_mkostemp.U:

This variable conditionally defines HAS_MKOSTEMP if mkostemp() is available to exclusively create and open a uniquely named (with a suffix) temporary file.

d_mkstemp

From d_mkstemp.U:

This variable conditionally defines the HAS_MKSTEMP symbol, which indicates to the C program that the mkstemp() routine is available to exclusively create and open a uniquely named temporary file.

d_mkstemps

From d_mkstemps.U:

This variable conditionally defines the HAS_MKSTEMPS symbol, which indicates to the C program that the mkstemps() routine is available to exclusively create and open a uniquely named (with a suffix) temporary file.

d_mktime

From d_mktime.U:

This variable conditionally defines the HAS_MKTIME symbol, which indicates to the C program that the mktime() routine is available.

d_mktime64

From d_timefuncs64.U:

This variable conditionally defines the HAS_MKTIME64 symbol, which indicates to the C program that the mktime64 () routine is available.

d_mmap

From d_mmap.U:

This variable conditionally defines HAS_MMAP if mmap() is available to map a file into memory.

d_modfl

From d_modfl.U:

This variable conditionally defines the HAS_MODFL symbol, which indicates to the C program that the modfl() routine is available.

d_modflproto

From d_modfl.U:

This symbol, if defined, indicates that the system provides a prototype for the modfl() function. Otherwise, it is up to the program to supply one. C99 says it should be long double modfl(long double, long double *);

d_mprotect

From d_mprotect.U:

This variable conditionally defines HAS_MPROTECT if mprotect() is available to modify the access protection of a memory mapped file.

d_msg

From d_msg.U:

This variable conditionally defines the HAS_MSG symbol, which indicates that the entire msg*(2) library is present.

d_msg_ctrunc

From d_socket.U:

This variable conditionally defines the HAS_MSG_CTRUNC symbol, which indicates that the MSG_CTRUNC is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_dontroute

From d_socket.U:

This variable conditionally defines the HAS_MSG_DONTROUTE symbol, which indicates that the MSG_DONTROUTE is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_oob

From d_socket.U:

This variable conditionally defines the HAS_MSG_OOB symbol, which indicates that the MSG_OOB is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_peek

From d_socket.U:

This variable conditionally defines the HAS_MSG_PEEK symbol, which indicates that the MSG_PEEK is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_proxy

From d_socket.U:

This variable conditionally defines the HAS_MSG_PROXY symbol, which indicates that the MSG_PROXY is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msgctl

From d_msgctl.U:

This variable conditionally defines the HAS_MSGCTL symbol, which indicates to the C program that the msgctl() routine is available.

d_msgget

From d_msgget.U:

This variable conditionally defines the HAS_MSGGET symbol, which indicates to the C program that the msgget() routine is available.

d_msghdr_s

From d_msghdr_s.U:

This variable conditionally defines the HAS_STRUCT_MSGHDR symbol, which indicates that the struct msghdr is supported.

d_msgrcv

From d_msgrcv.U:

This variable conditionally defines the HAS_MSGRCV symbol, which indicates to the C program that the msgrcv() routine is available.

d_msgsnd

From d_msgsnd.U:

This variable conditionally defines the HAS_MSGSND symbol, which indicates to the C program that the msgsnd() routine is available.

d_msync

From d_msync.U:

This variable conditionally defines HAS_MSYNC if msync() is available to synchronize a mapped file.

d_munmap

From d_munmap.U:

This variable conditionally defines HAS_MUNMAP if munmap() is available to unmap a region mapped by mmap().

d_mymalloc

From mallocsrc.U:

This variable conditionally defines MYMALLOC in case other parts of the source want to take special action if MYMALLOC is used. This may include different sorts of profiling or error detection.

d_nan

From d_nan.U:

This variable conditionally defines HAS_NAN if nan() is available to generate NaN.

d_nanosleep

From d_nanosleep.U:

This variable conditionally defines HAS_NANOSLEEP if nanosleep() is available to sleep with 1E-9 sec accuracy.

d_ndbm

From i_ndbm.U:

This variable conditionally defines the HAS_NDBM symbol, which indicates that both the ndbm.h include file and an appropriate ndbm library exist. Consult the different i_*ndbm variables to find out the actual include location. Sometimes, a system has the header file but not the library. This variable will only be set if the system has both.

d_ndbm_h_uses_prototypes

From i_ndbm.U:

This variable conditionally defines the NDBM_H_USES_PROTOTYPES symbol, which indicates that the ndbm.h include file uses real ANSI C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_nearbyint

From d_nearbyint.U:

This variable conditionally defines HAS_NEARBYINT if nearbyint() is available to return the integral value closest to (according to the current rounding mode) to x.

d_newlocale

From d_newlocale.U:

This variable conditionally defines the HAS_NEWLOCALE symbol, which indicates to the C program that the newlocale() routine is available to return a new locale object or modify an existing locale object.

d_nextafter

From d_nextafter.U:

This variable conditionally defines HAS_NEXTAFTER if nextafter() is available to return the next machine representable double from x in direction y.

d_nexttoward

From d_nexttoward.U:

This variable conditionally defines HAS_NEXTTOWARD if nexttoward() is available to return the next machine representable long double from x in direction y.

d_nice

From d_nice.U:

This variable conditionally defines the HAS_NICE symbol, which indicates to the C program that the nice() routine is available.

d_nl_langinfo

From d_nl_langinfo.U:

This variable conditionally defines the HAS_NL_LANGINFO symbol, which indicates to the C program that the nl_langinfo() routine is available.

d_nl_langinfo_l

From d_nl_langinfo.U:

This variable conditionally defines the HAS_NL_LANGINFO_L symbol, which indicates to the C program that the nl_langinfo_l() routine is available.

d_non_int_bitfields

From d_bitfield.U:

This variable conditionally defines HAS_NON_INT_BITFIELDS which indicates that the C compiler accepts struct bitfields of sizes that aren't int or unsigned int

d_nv_preserves_uv

From perlxv.U:

This variable indicates whether a variable of type nvtype can preserve all the bits a variable of type uvtype.

d_nv_zero_is_allbits_zero

From perlxv.U:

This variable indicates whether a variable of type nvtype stores 0.0 in memory as all bits zero.

d_off64_t

From d_off64_t.U:

This symbol will be defined if the C compiler supports off64_t.

d_old_pthread_create_joinable

From d_pthrattrj.U:

This variable conditionally defines pthread_create_joinable. undef if pthread.h defines PTHREAD_CREATE_JOINABLE.

d_oldpthreads

From usethreads.U:

This variable conditionally defines the OLD_PTHREADS_API symbol, and indicates that Perl should be built to use the old draft POSIX threads API. This is only potentially meaningful if usethreads is set.

d_oldsock

From d_socket.U:

This variable conditionally defines the OLDSOCKET symbol, which indicates that the BSD socket interface is based on 4.1c and not 4.2.

d_open3

From d_open3.U:

This variable conditionally defines the HAS_OPEN3 manifest constant, which indicates to the C program that the 3 argument version of the open(2) function is available.

d_openat

From d_fsat.U:

This variable conditionally defines the HAS_OPENAT symbol, which indicates the POSIX openat() function is available.

d_pathconf

From d_pathconf.U:

This variable conditionally defines the HAS_PATHCONF symbol, which indicates to the C program that the pathconf() routine is available to determine file-system related limits and options associated with a given filename.

d_pause

From d_pause.U:

This variable conditionally defines the HAS_PAUSE symbol, which indicates to the C program that the pause() routine is available to suspend a process until a signal is received.

d_perl_lc_all_category_positions_init

From disparate_lc_all.U:

This symbol, if defined, indicates that $lc_all_category_positions_init is valid

d_perl_lc_all_separator

From disparate_lc_all.U:

This symbol, if defined, indicates that $perl_lc_all_separator is valid

d_perl_lc_all_uses_name_value_pairs

From disparate_lc_all.U:

This symbol, if defined, indicates that the string returned by setlocale(LC_ALL, NULL) uses name=value; pairs to indicate what each category's locale is when they aren't all set to the same locale. When not defined, the platform uses positional notation.

d_perl_otherlibdirs

From otherlibdirs.U:

This variable conditionally defines PERL_OTHERLIBDIRS, which contains a colon-separated set of paths for the perl binary to include in @INC. See also otherlibdirs.

d_phostname

From d_gethname.U:

This variable conditionally defines the HAS_PHOSTNAME symbol, which contains the shell command which, when fed to popen(), may be used to derive the host name.

d_pipe

From d_pipe.U:

This variable conditionally defines the HAS_PIPE symbol, which indicates to the C program that the pipe() routine is available to create an inter-process channel.

d_pipe2

From d_pipe2.U:

This variable conditionally defines the HAS_PIPE2 symbol, which indicates to the C program that the pipe2() routine is available to create an inter-process channel.

d_poll

From d_poll.U:

This variable conditionally defines the HAS_POLL symbol, which indicates to the C program that the poll() routine is available to poll active file descriptors.

d_portable

From d_portable.U:

This variable conditionally defines the PORTABLE symbol, which indicates to the C program that it should not assume that it is running on the machine it was compiled on.

d_prctl

From d_prctl.U:

This variable conditionally defines the HAS_PRCTL symbol, which indicates to the C program that the prctl() routine is available. Note that there are at least two prctl variants: Linux and Irix. While they are somewhat similar, they are incompatible.

d_prctl_set_name

From d_prctl.U:

This variable conditionally defines the HAS_PRCTL_SET_NAME symbol, which indicates to the C program that the prctl() routine supports the PR_SET_NAME option.

d_printf_format_null

From d_attribut.U:

This variable conditionally defines PRINTF_FORMAT_NULL_OK, which indicates the C compiler allows printf-like formats to be null.

d_procselfexe

From d_procselfexe.U:

Defined if $procselfexe is symlink to the absolute pathname of the executing program.

d_pseudofork

From d_vfork.U:

This variable conditionally defines the HAS_PSEUDOFORK symbol, which indicates that an emulation of the fork routine is available.

d_pthread_atfork

From d_pthread_atfork.U:

This variable conditionally defines the HAS_PTHREAD_ATFORK symbol, which indicates to the C program that the pthread_atfork() routine is available.

d_pthread_attr_setscope

From d_pthread_attr_ss.U:

This variable conditionally defines HAS_PTHREAD_ATTR_SETSCOPE if pthread_attr_setscope() is available to set the contention scope attribute of a thread attribute object.

d_pthread_yield

From d_pthread_y.U:

This variable conditionally defines the HAS_PTHREAD_YIELD symbol if the pthread_yield routine is available to yield the execution of the current thread.

d_ptrdiff_t

From d_ptrdiff_t.U:

This symbol will be defined if the C compiler supports ptrdiff_t.

d_pwage

From i_pwd.U:

This variable conditionally defines PWAGE, which indicates that struct passwd contains pw_age.

d_pwchange

From i_pwd.U:

This variable conditionally defines PWCHANGE, which indicates that struct passwd contains pw_change.

d_pwclass

From i_pwd.U:

This variable conditionally defines PWCLASS, which indicates that struct passwd contains pw_class.

d_pwcomment

From i_pwd.U:

This variable conditionally defines PWCOMMENT, which indicates that struct passwd contains pw_comment.

d_pwexpire

From i_pwd.U:

This variable conditionally defines PWEXPIRE, which indicates that struct passwd contains pw_expire.

d_pwgecos

From i_pwd.U:

This variable conditionally defines PWGECOS, which indicates that struct passwd contains pw_gecos.

d_pwpasswd

From i_pwd.U:

This variable conditionally defines PWPASSWD, which indicates that struct passwd contains pw_passwd.

d_pwquota

From i_pwd.U:

This variable conditionally defines PWQUOTA, which indicates that struct passwd contains pw_quota.

d_qgcvt

From d_qgcvt.U:

This variable conditionally defines the HAS_QGCVT symbol, which indicates to the C program that the qgcvt() routine is available.

d_quad

From quadtype.U:

This variable, if defined, tells that there's a 64-bit integer type, quadtype.

d_querylocale

From d_newlocale.U:

This variable conditionally defines the HAS_QUERYLOCALE symbol, which indicates to the C program that the querylocale() routine is available to return the name of the locale for a category mask.

d_random_r

From d_random_r.U:

This variable conditionally defines the HAS_RANDOM_R symbol, which indicates to the C program that the random_r() routine is available.

d_re_comp

From d_regcmp.U:

This variable conditionally defines the HAS_RECOMP symbol, which indicates to the C program that the re_comp() routine is available for regular pattern matching (usually on BSD). If so, it is likely that re_exec() exists.

d_readdir

From d_readdir.U:

This variable conditionally defines HAS_READDIR if readdir() is available to read directory entries.

d_readdir64_r

From d_readdir64_r.U:

This variable conditionally defines the HAS_READDIR64_R symbol, which indicates to the C program that the readdir64_r() routine is available.

d_readdir_r

From d_readdir_r.U:

This variable conditionally defines the HAS_READDIR_R symbol, which indicates to the C program that the readdir_r() routine is available.

From d_readlink.U:

This variable conditionally defines the HAS_READLINK symbol, which indicates to the C program that the readlink() routine is available to read the value of a symbolic link.

d_readv

From d_readv.U:

This variable conditionally defines the HAS_READV symbol, which indicates to the C program that the readv() routine is available.

d_recvmsg

From d_recvmsg.U:

This variable conditionally defines the HAS_RECVMSG symbol, which indicates to the C program that the recvmsg() routine is available.

d_regcmp

From d_regcmp.U:

This variable conditionally defines the HAS_REGCMP symbol, which indicates to the C program that the regcmp() routine is available for regular pattern matching (usually on System V).

d_regcomp

From d_regcmp.U:

This variable conditionally defines the HAS_REGCOMP symbol, which indicates to the C program that the regcomp() routine is available for regular pattern matching (usually on POSIX.2 conforming systems).

d_remainder

From d_remainder.U:

This variable conditionally defines the HAS_REMAINDER symbol, which indicates to the C program that the remainder() routine is available.

d_remquo

From d_remquo.U:

This variable conditionally defines the HAS_REMQUO symbol, which indicates to the C program that the remquo() routine is available.

d_rename

From d_rename.U:

This variable conditionally defines the HAS_RENAME symbol, which indicates to the C program that the rename() routine is available to rename files.

d_renameat

From d_fsat.U:

This variable conditionally defines the HAS_RENAMEAT symbol, which indicates the POSIX renameat() function is available.

d_rewinddir

From d_readdir.U:

This variable conditionally defines HAS_REWINDDIR if rewinddir() is available.

d_rint

From d_rint.U:

This variable conditionally defines the HAS_RINT symbol, which indicates to the C program that the rint() routine is available.

d_rmdir

From d_rmdir.U:

This variable conditionally defines HAS_RMDIR if rmdir() is available to remove directories.

d_round

From d_round.U:

This variable conditionally defines the HAS_ROUND symbol, which indicates to the C program that the round() routine is available.

d_sbrkproto

From d_sbrkproto.U:

This variable conditionally defines the HAS_SBRK_PROTO symbol, which indicates to the C program that the system provides a prototype for the sbrk() function. Otherwise, it is up to the program to supply one.

d_scalbn

From d_scalbn.U:

This variable conditionally defines the HAS_SCALBN symbol, which indicates to the C program that the scalbn() routine is available.

d_scalbnl

From d_scalbnl.U:

This variable conditionally defines the HAS_SCALBNL symbol, which indicates to the C program that the scalbnl() routine is available. If ilogbl is also present we can emulate frexpl.

d_sched_yield

From d_pthread_y.U:

This variable conditionally defines the HAS_SCHED_YIELD symbol if the sched_yield routine is available to yield the execution of the current thread.

d_scm_rights

From d_socket.U:

This variable conditionally defines the HAS_SCM_RIGHTS symbol, which indicates that the SCM_RIGHTS is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_seekdir

From d_readdir.U:

This variable conditionally defines HAS_SEEKDIR if seekdir() is available.

d_select

From d_select.U:

This variable conditionally defines HAS_SELECT if select() is available to select active file descriptors. A <sys/time.h> inclusion may be necessary for the timeout field.

d_sem

From d_sem.U:

This variable conditionally defines the HAS_SEM symbol, which indicates that the entire sem*(2) library is present.

d_semctl

From d_semctl.U:

This variable conditionally defines the HAS_SEMCTL symbol, which indicates to the C program that the semctl() routine is available.

d_semctl_semid_ds

From d_union_semun.U:

This variable conditionally defines USE_SEMCTL_SEMID_DS, which indicates that struct semid_ds * is to be used for semctl IPC_STAT.

d_semctl_semun

From d_union_semun.U:

This variable conditionally defines USE_SEMCTL_SEMUN, which indicates that union semun is to be used for semctl IPC_STAT.

d_semget

From d_semget.U:

This variable conditionally defines the HAS_SEMGET symbol, which indicates to the C program that the semget() routine is available.

d_semop

From d_semop.U:

This variable conditionally defines the HAS_SEMOP symbol, which indicates to the C program that the semop() routine is available.

d_sendmsg

From d_sendmsg.U:

This variable conditionally defines the HAS_SENDMSG symbol, which indicates to the C program that the sendmsg() routine is available.

d_setegid

From d_setegid.U:

This variable conditionally defines the HAS_SETEGID symbol, which indicates to the C program that the setegid() routine is available to change the effective gid of the current program.

d_setenv

From d_setenv.U:

This variable conditionally defines the HAS_SETENV symbol, which indicates to the C program that the setenv routine is available.

d_seteuid

From d_seteuid.U:

This variable conditionally defines the HAS_SETEUID symbol, which indicates to the C program that the seteuid() routine is available to change the effective uid of the current program.

d_setgrent

From d_setgrent.U:

This variable conditionally defines the HAS_SETGRENT symbol, which indicates to the C program that the setgrent() routine is available for initializing sequential access to the group database.

d_setgrent_r

From d_setgrent_r.U:

This variable conditionally defines the HAS_SETGRENT_R symbol, which indicates to the C program that the setgrent_r() routine is available.

d_setgrps

From d_setgrps.U:

This variable conditionally defines the HAS_SETGROUPS symbol, which indicates to the C program that the setgroups() routine is available to set the list of process groups.

d_sethent

From d_sethent.U:

This variable conditionally defines HAS_SETHOSTENT if sethostent() is available.

d_sethostent_r

From d_sethostent_r.U:

This variable conditionally defines the HAS_SETHOSTENT_R symbol, which indicates to the C program that the sethostent_r() routine is available.

d_setitimer

From d_setitimer.U:

This variable conditionally defines the HAS_SETITIMER symbol, which indicates to the C program that the setitimer() routine is available.

d_setlinebuf

From d_setlnbuf.U:

This variable conditionally defines the HAS_SETLINEBUF symbol, which indicates to the C program that the setlinebuf() routine is available to change stderr or stdout from block-buffered or unbuffered to a line-buffered mode.

d_setlocale

From d_setlocale.U:

This variable conditionally defines HAS_SETLOCALE if setlocale() is available to handle locale-specific ctype implementations.

d_setlocale_accepts_any_locale_name

From d_setlocale.U:

This variable conditionally defines SETLOCALE_ACCEPTS_ANY_LOCALE_NAME if setlocale() accepts any locale name.

d_setlocale_r

From d_setlocale_r.U:

This variable conditionally defines the HAS_SETLOCALE_R symbol, which indicates to the C program that the setlocale_r() routine is available.

d_setnent

From d_setnent.U:

This variable conditionally defines HAS_SETNETENT if setnetent() is available.

d_setnetent_r

From d_setnetent_r.U:

This variable conditionally defines the HAS_SETNETENT_R symbol, which indicates to the C program that the setnetent_r() routine is available.

d_setpent

From d_setpent.U:

This variable conditionally defines HAS_SETPROTOENT if setprotoent() is available.

d_setpgid

From d_setpgid.U:

This variable conditionally defines the HAS_SETPGID symbol if the setpgid(pid, gpid) function is available to set process group ID.

d_setpgrp

From d_setpgrp.U:

This variable conditionally defines HAS_SETPGRP if setpgrp() is available to set the current process group.

d_setpgrp2

From d_setpgrp2.U:

This variable conditionally defines the HAS_SETPGRP2 symbol, which indicates to the C program that the setpgrp2() (as in DG/UX) routine is available to set the current process group.

d_setprior

From d_setprior.U:

This variable conditionally defines HAS_SETPRIORITY if setpriority() is available to set a process's priority.

d_setproctitle

From d_setproctitle.U:

This variable conditionally defines the HAS_SETPROCTITLE symbol, which indicates to the C program that the setproctitle() routine is available.

d_setprotoent_r

From d_setprotoent_r.U:

This variable conditionally defines the HAS_SETPROTOENT_R symbol, which indicates to the C program that the setprotoent_r() routine is available.

d_setpwent

From d_setpwent.U:

This variable conditionally defines the HAS_SETPWENT symbol, which indicates to the C program that the setpwent() routine is available for initializing sequential access to the passwd database.

d_setpwent_r

From d_setpwent_r.U:

This variable conditionally defines the HAS_SETPWENT_R symbol, which indicates to the C program that the setpwent_r() routine is available.

d_setregid

From d_setregid.U:

This variable conditionally defines HAS_SETREGID if setregid() is available to change the real and effective gid of the current process.

d_setresgid

From d_setregid.U:

This variable conditionally defines HAS_SETRESGID if setresgid() is available to change the real, effective and saved gid of the current process.

d_setresuid

From d_setreuid.U:

This variable conditionally defines HAS_SETREUID if setresuid() is available to change the real, effective and saved uid of the current process.

d_setreuid

From d_setreuid.U:

This variable conditionally defines HAS_SETREUID if setreuid() is available to change the real and effective uid of the current process.

d_setrgid

From d_setrgid.U:

This variable conditionally defines the HAS_SETRGID symbol, which indicates to the C program that the setrgid() routine is available to change the real gid of the current program.

d_setruid

From d_setruid.U:

This variable conditionally defines the HAS_SETRUID symbol, which indicates to the C program that the setruid() routine is available to change the real uid of the current program.

d_setsent

From d_setsent.U:

This variable conditionally defines HAS_SETSERVENT if setservent() is available.

d_setservent_r

From d_setservent_r.U:

This variable conditionally defines the HAS_SETSERVENT_R symbol, which indicates to the C program that the setservent_r() routine is available.

d_setsid

From d_setsid.U:

This variable conditionally defines HAS_SETSID if setsid() is available to set the process group ID.

d_setvbuf

From d_setvbuf.U:

This variable conditionally defines the HAS_SETVBUF symbol, which indicates to the C program that the setvbuf() routine is available to change buffering on an open stdio stream.

d_shm

From d_shm.U:

This variable conditionally defines the HAS_SHM symbol, which indicates that the entire shm*(2) library is present.

d_shmat

From d_shmat.U:

This variable conditionally defines the HAS_SHMAT symbol, which indicates to the C program that the shmat() routine is available.

d_shmatprototype

From d_shmat.U:

This variable conditionally defines the HAS_SHMAT_PROTOTYPE symbol, which indicates that sys/shm.h has a prototype for shmat.

d_shmctl

From d_shmctl.U:

This variable conditionally defines the HAS_SHMCTL symbol, which indicates to the C program that the shmctl() routine is available.

d_shmdt

From d_shmdt.U:

This variable conditionally defines the HAS_SHMDT symbol, which indicates to the C program that the shmdt() routine is available.

d_shmget

From d_shmget.U:

This variable conditionally defines the HAS_SHMGET symbol, which indicates to the C program that the shmget() routine is available.

d_sigaction

From d_sigaction.U:

This variable conditionally defines the HAS_SIGACTION symbol, which indicates that the Vr4 sigaction() routine is available.

d_siginfo_si_addr

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_ADDR symbol, which indicates that the siginfo_t struct has the si_addr member.

d_siginfo_si_band

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_BAND symbol, which indicates that the siginfo_t struct has the si_band member.

d_siginfo_si_errno

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_ERRNO symbol, which indicates that the siginfo_t struct has the si_errno member.

d_siginfo_si_fd

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_FD symbol, which indicates that the siginfo_t struct has the si_fd member.

d_siginfo_si_pid

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_PID symbol, which indicates that the siginfo_t struct has the si_pid member.

d_siginfo_si_status

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_STATUS symbol, which indicates that the siginfo_t struct has the si_status member.

d_siginfo_si_uid

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_UID symbol, which indicates that the siginfo_t struct has the si_uid member.

d_siginfo_si_value

From d_siginfo_si.U:

This variable conditionally defines the HAS_SIGINFO_SI_VALUE symbol, which indicates that the siginfo_t struct has the si_value member.

d_signbit

From d_signbit.U:

This variable conditionally defines the HAS_SIGNBIT symbol, which indicates to the C program that the signbit() routine is available and safe to use with perl's intern NV type.

d_sigprocmask

From d_sigprocmask.U:

This variable conditionally defines HAS_SIGPROCMASK if sigprocmask() is available to examine or change the signal mask of the calling process.

d_sigsetjmp

From d_sigsetjmp.U:

This variable conditionally defines the HAS_SIGSETJMP symbol, which indicates that the sigsetjmp() routine is available to call setjmp() and optionally save the process's signal mask.

d_sin6_scope_id

From d_socket.U:

This variable conditionally defines the HAS_SIN6_SCOPE_ID symbol, which indicates that a struct sockaddr_in6 structure has the sin6_scope_id member.

d_sitearch

From sitearch.U:

This variable conditionally defines SITEARCH to hold the pathname of architecture-dependent library files for $package. If $sitearch is the same as $archlib, then this is set to undef.

d_snprintf

From d_snprintf.U:

This variable conditionally defines the HAS_SNPRINTF symbol, which indicates to the C program that the snprintf () library function is available.

d_sockaddr_in6

From d_socket.U:

This variable conditionally defines the HAS_SOCKADDR_IN6 symbol, which indicates the availability of a struct sockaddr_in6.

d_sockaddr_sa_len

From d_socket.U:

This variable conditionally defines the HAS_SOCKADDR_SA_LEN symbol, which indicates that a struct sockaddr structure has the sa_len member.

d_sockaddr_storage

From d_socket.U:

This variable conditionally defines the HAS_SOCKADDR_STORAGE symbol, which indicates the availability of a struct sockaddr_storage.

d_sockatmark

From d_sockatmark.U:

This variable conditionally defines the HAS_SOCKATMARK symbol, which indicates to the C program that the sockatmark() routine is available.

d_sockatmarkproto

From d_sockatmarkproto.U:

This variable conditionally defines the HAS_SOCKATMARK_PROTO symbol, which indicates to the C program that the system provides a prototype for the sockatmark() function. Otherwise, it is up to the program to supply one.

d_socket

From d_socket.U:

This variable conditionally defines HAS_SOCKET, which indicates that the BSD socket interface is supported.

d_socklen_t

From d_socklen_t.U:

This symbol will be defined if the C compiler supports socklen_t.

d_sockpair

From d_socket.U:

This variable conditionally defines the HAS_SOCKETPAIR symbol, which indicates that the BSD socketpair() is supported.

d_socks5_init

From d_socks5_init.U:

This variable conditionally defines the HAS_SOCKS5_INIT symbol, which indicates to the C program that the socks5_init() routine is available.

d_sqrtl

From d_sqrtl.U:

This variable conditionally defines the HAS_SQRTL symbol, which indicates to the C program that the sqrtl() routine is available.

d_srand48_r

From d_srand48_r.U:

This variable conditionally defines the HAS_SRAND48_R symbol, which indicates to the C program that the srand48_r() routine is available.

d_srandom_r

From d_srandom_r.U:

This variable conditionally defines the HAS_SRANDOM_R symbol, which indicates to the C program that the srandom_r() routine is available.

d_sresgproto

From d_sresgproto.U:

This variable conditionally defines the HAS_SETRESGID_PROTO symbol, which indicates to the C program that the system provides a prototype for the setresgid() function. Otherwise, it is up to the program to supply one.

d_sresuproto

From d_sresuproto.U:

This variable conditionally defines the HAS_SETRESUID_PROTO symbol, which indicates to the C program that the system provides a prototype for the setresuid() function. Otherwise, it is up to the program to supply one.

d_stat

From d_stat.U:

This variable conditionally defines HAS_STAT if stat() is available to get file status.

d_statblks

From d_statblks.U:

This variable conditionally defines USE_STAT_BLOCKS if this system has a stat structure declaring st_blksize and st_blocks.

d_statfs_f_flags

From d_statfs_f_flags.U:

This variable conditionally defines the HAS_STRUCT_STATFS_F_FLAGS symbol, which indicates to struct statfs from has f_flags member. This kind of struct statfs is coming from sys/mount.h (BSD), not from sys/statfs.h (SYSV).

d_statfs_s

From d_statfs_s.U:

This variable conditionally defines the HAS_STRUCT_STATFS symbol, which indicates that the struct statfs is supported.

d_static_inline

From d_static_inline.U:

This variable conditionally defines the HAS_STATIC_INLINE symbol, which indicates that the C compiler supports C99-style static inline. That is, the function can't be called from another translation unit.

d_statvfs

From d_statvfs.U:

This variable conditionally defines the HAS_STATVFS symbol, which indicates to the C program that the statvfs() routine is available.

d_stdio_cnt_lval

From d_stdstdio.U:

This variable conditionally defines STDIO_CNT_LVALUE if the FILE_cnt macro can be used as an lvalue.

d_stdio_ptr_lval

From d_stdstdio.U:

This variable conditionally defines STDIO_PTR_LVALUE if the FILE_ptr macro can be used as an lvalue.

d_stdio_ptr_lval_nochange_cnt

From d_stdstdio.U:

This symbol is defined if using the FILE_ptr macro as an lvalue to increase the pointer by n leaves File_cnt(fp) unchanged.

d_stdio_ptr_lval_sets_cnt

From d_stdstdio.U:

This symbol is defined if using the FILE_ptr macro as an lvalue to increase the pointer by n has the side effect of decreasing the value of File_cnt(fp) by n.

d_stdio_stream_array

From stdio_streams.U:

This variable tells whether there is an array holding the stdio streams.

d_stdiobase

From d_stdstdio.U:

This variable conditionally defines USE_STDIO_BASE if this system has a FILE structure declaring a usable _base field (or equivalent) in stdio.h.

d_stdstdio

From d_stdstdio.U:

This variable conditionally defines USE_STDIO_PTR if this system has a FILE structure declaring usable _ptr and _cnt fields (or equivalent) in stdio.h.

d_strcoll

From d_strcoll.U:

This variable conditionally defines HAS_STRCOLL if strcoll() is available to compare strings using collating information.

d_strerror_l

From d_strerror_l.U:

This variable conditionally defines the HAS_STRERROR_L symbol, which indicates to the C program that the strerror_l() routine is available to return the error message for a given errno value in a particular locale (identified by a locale_t object).

d_strerror_r

From d_strerror_r.U:

This variable conditionally defines the HAS_STRERROR_R symbol, which indicates to the C program that the strerror_r() routine is available.

d_strftime

From d_strftime.U:

This variable conditionally defines the HAS_STRFTIME symbol, which indicates to the C program that the strftime() routine is available.

d_strlcat

From d_strlcat.U:

This variable conditionally defines the HAS_STRLCAT symbol, which indicates to the C program that the strlcat () routine is available.

d_strlcpy

From d_strlcpy.U:

This variable conditionally defines the HAS_STRLCPY symbol, which indicates to the C program that the strlcpy () routine is available.

d_strnlen

From d_strnlen.U:

This variable conditionally defines the HAS_STRNLEN symbol, which indicates to the C program that the strnlen () routine is available.

d_strtod

From d_strtod.U:

This variable conditionally defines the HAS_STRTOD symbol, which indicates to the C program that the strtod() routine is available to provide better numeric string conversion than atof().

d_strtod_l

From d_strtod_l.U:

This variable conditionally defines the HAS_STRTOD_L symbol, which indicates to the C program that the strtod_l() routine is available.

d_strtol

From d_strtol.U:

This variable conditionally defines the HAS_STRTOL symbol, which indicates to the C program that the strtol() routine is available to provide better numeric string conversion than atoi() and friends.

d_strtold

From d_strtold.U:

This variable conditionally defines the HAS_STRTOLD symbol, which indicates to the C program that the strtold() routine is available.

d_strtold_l

From d_strtold_l.U:

This variable conditionally defines the HAS_STRTOLD_L symbol, which indicates to the C program that the strtold_l() routine is available.

d_strtoll

From d_strtoll.U:

This variable conditionally defines the HAS_STRTOLL symbol, which indicates to the C program that the strtoll() routine is available.

d_strtoq

From d_strtoq.U:

This variable conditionally defines the HAS_STRTOQ symbol, which indicates to the C program that the strtoq() routine is available.

d_strtoul

From d_strtoul.U:

This variable conditionally defines the HAS_STRTOUL symbol, which indicates to the C program that the strtoul() routine is available to provide conversion of strings to unsigned long.

d_strtoull

From d_strtoull.U:

This variable conditionally defines the HAS_STRTOULL symbol, which indicates to the C program that the strtoull() routine is available.

d_strtouq

From d_strtouq.U:

This variable conditionally defines the HAS_STRTOUQ symbol, which indicates to the C program that the strtouq() routine is available.

d_strxfrm

From d_strxfrm.U:

This variable conditionally defines HAS_STRXFRM if strxfrm() is available to transform strings.

d_strxfrm_l

From d_strxfrm_l.U:

This variable conditionally defines HAS_STRXFRM_L if strxfrm_l() is available to transform strings.

d_suidsafe

From d_dosuid.U:

This variable conditionally defines SETUID_SCRIPTS_ARE_SECURE_NOW if setuid scripts can be secure. This test looks in /dev/fd/.

From d_symlink.U:

This variable conditionally defines the HAS_SYMLINK symbol, which indicates to the C program that the symlink() routine is available to create symbolic links.

d_syscall

From d_syscall.U:

This variable conditionally defines HAS_SYSCALL if syscall() is available call arbitrary system calls.

d_syscallproto

From d_syscallproto.U:

This variable conditionally defines the HAS_SYSCALL_PROTO symbol, which indicates to the C program that the system provides a prototype for the syscall() function. Otherwise, it is up to the program to supply one.

d_sysconf

From d_sysconf.U:

This variable conditionally defines the HAS_SYSCONF symbol, which indicates to the C program that the sysconf() routine is available to determine system related limits and options.

d_sysernlst

From d_strerror.U:

This variable conditionally defines HAS_SYS_ERRNOLIST if sys_errnolist[] is available to translate error numbers to the symbolic name.

d_syserrlst

From d_strerror.U:

This variable conditionally defines HAS_SYS_ERRLIST if sys_errlist[] is available to translate error numbers to strings.

d_system

From d_system.U:

This variable conditionally defines HAS_SYSTEM if system() is available to issue a shell command.

d_tcgetpgrp

From d_tcgtpgrp.U:

This variable conditionally defines the HAS_TCGETPGRP symbol, which indicates to the C program that the tcgetpgrp() routine is available. to get foreground process group ID.

d_tcsetpgrp

From d_tcstpgrp.U:

This variable conditionally defines the HAS_TCSETPGRP symbol, which indicates to the C program that the tcsetpgrp() routine is available to set foreground process group ID.

d_telldir

From d_readdir.U:

This variable conditionally defines HAS_TELLDIR if telldir() is available.

d_telldirproto

From d_telldirproto.U:

This variable conditionally defines the HAS_TELLDIR_PROTO symbol, which indicates to the C program that the system provides a prototype for the telldir() function. Otherwise, it is up to the program to supply one.

d_tgamma

From d_tgamma.U:

This variable conditionally defines the HAS_TGAMMA symbol, which indicates to the C program that the tgamma() routine is available for the gamma function. See also d_lgamma.

d_thread_local

From d_thread_local.U:

This variable conditionally defines the PERL_THREAD_LOCAL symbol. In turn that gives a linkage specification for thread-local storage.

d_time

From d_time.U:

This variable conditionally defines the HAS_TIME symbol, which indicates that the time() routine exists. The time() routine is normally provided on UNIX systems.

d_timegm

From d_timegm.U:

This variable conditionally defines the HAS_TIMEGM symbol, which indicates to the C program that the timegm () routine is available.

d_times

From d_times.U:

This variable conditionally defines the HAS_TIMES symbol, which indicates that the times() routine exists. The times() routine is normally provided on UNIX systems. You may have to include <sys/times.h>.

d_tm_tm_gmtoff

From i_time.U:

This variable conditionally defines HAS_TM_TM_GMTOFF, which indicates to the C program that the struct tm has the tm_gmtoff field.

d_tm_tm_zone

From i_time.U:

This variable conditionally defines HAS_TM_TM_ZONE, which indicates to the C program that the struct tm has the tm_zone field.

d_tmpnam_r

From d_tmpnam_r.U:

This variable conditionally defines the HAS_TMPNAM_R symbol, which indicates to the C program that the tmpnam_r() routine is available.

d_towlower

From d_towlower.U:

This variable conditionally defines the HAS_TOWLOWER symbol, which indicates to the C program that the towlower() routine is available.

d_towupper

From d_towupper.U:

This variable conditionally defines the HAS_TOWUPPER symbol, which indicates to the C program that the towupper() routine is available.

d_trunc

From d_trunc.U:

This variable conditionally defines the HAS_TRUNC symbol, which indicates to the C program that the trunc() routine is available to round doubles towards zero.

d_truncate

From d_truncate.U:

This variable conditionally defines HAS_TRUNCATE if truncate() is available to truncate files.

d_truncl

From d_truncl.U:

This variable conditionally defines the HAS_TRUNCL symbol, which indicates to the C program that the truncl() routine is available to round long doubles towards zero. If copysignl is also present, we can emulate modfl.

d_ttyname_r

From d_ttyname_r.U:

This variable conditionally defines the HAS_TTYNAME_R symbol, which indicates to the C program that the ttyname_r() routine is available.

d_tzname

From d_tzname.U:

This variable conditionally defines HAS_TZNAME if tzname[] is available to access timezone names.

d_u32align

From d_u32align.U:

This variable tells whether you must access character data through U32-aligned pointers.

d_ualarm

From d_ualarm.U:

This variable conditionally defines the HAS_UALARM symbol, which indicates to the C program that the ualarm() routine is available.

d_umask

From d_umask.U:

This variable conditionally defines the HAS_UMASK symbol, which indicates to the C program that the umask() routine is available. to set and get the value of the file creation mask.

d_uname

From d_gethname.U:

This variable conditionally defines the HAS_UNAME symbol, which indicates to the C program that the uname() routine may be used to derive the host name.

d_union_semun

From d_union_semun.U:

This variable conditionally defines HAS_UNION_SEMUN if the union semun is defined by including <sys/sem.h>.

d_unlinkat

From d_fsat.U:

This variable conditionally defines the HAS_UNLINKAT symbol, which indicates the POSIX unlinkat() function isavailable.

d_unordered

From d_unordered.U:

This variable conditionally defines the HAS_UNORDERED symbol, which indicates to the C program that the unordered() routine is available.

d_unsetenv

From d_unsetenv.U:

This variable conditionally defines the HAS_UNSETENV symbol, which indicates to the C program that the unsetenv () routine is available.

d_uselocale

From d_newlocale.U:

This variable conditionally defines the HAS_USELOCALE symbol, which indicates to the C program that the uselocale() routine is available to set the current locale for the calling thread.

d_usleep

From d_usleep.U:

This variable conditionally defines HAS_USLEEP if usleep() is available to do high granularity sleeps.

d_usleepproto

From d_usleepproto.U:

This variable conditionally defines the HAS_USLEEP_PROTO symbol, which indicates to the C program that the system provides a prototype for the usleep() function. Otherwise, it is up to the program to supply one.

d_ustat

From d_ustat.U:

This variable conditionally defines HAS_USTAT if ustat() is available to query file system statistics by dev_t.

d_vendorarch

From vendorarch.U:

This variable conditionally defined PERL_VENDORARCH.

d_vendorbin

From vendorbin.U:

This variable conditionally defines PERL_VENDORBIN.

d_vendorlib

From vendorlib.U:

This variable conditionally defines PERL_VENDORLIB.

d_vendorscript

From vendorscript.U:

This variable conditionally defines PERL_VENDORSCRIPT.

d_vfork

From d_vfork.U:

This variable conditionally defines the HAS_VFORK symbol, which indicates the vfork() routine is available.

d_void_closedir

From d_closedir.U:

This variable conditionally defines VOID_CLOSEDIR if closedir() does not return a value.

d_voidsig

From d_voidsig.U:

This variable conditionally defines VOIDSIG if this system declares "void (*signal(...))()" in signal.h. The old way was to declare it as "int (*signal(...))()".

d_voidtty

From i_sysioctl.U:

This variable conditionally defines USE_IOCNOTTY to indicate that the ioctl() call with TIOCNOTTY should be used to void tty association. Otherwise (on USG probably), it is enough to close the standard file descriptors and do a setpgrp().

d_vsnprintf

From d_snprintf.U:

This variable conditionally defines the HAS_VSNPRINTF symbol, which indicates to the C program that the vsnprintf () library function is available.

d_wait4

From d_wait4.U:

This variable conditionally defines the HAS_WAIT4 symbol, which indicates the wait4() routine is available.

d_waitpid

From d_waitpid.U:

This variable conditionally defines HAS_WAITPID if waitpid() is available to wait for child process.

d_wcrtomb

From d_wcrtomb.U:

This variable conditionally defines the HAS_WCRTOMB symbol if the wcrtomb() routine is available to be used to convert a wide character into a multi-byte character.

d_wcscmp

From d_wcscmp.U:

This variable conditionally defines the HAS_WCSCMP symbol if the wcscmp() routine is available and can be used to compare wide character strings.

d_wcstombs

From d_wcstombs.U:

This variable conditionally defines the HAS_WCSTOMBS symbol, which indicates to the C program that the wcstombs() routine is available to convert wide character strings to multibyte strings.

d_wcsxfrm

From d_wcsxfrm.U:

This variable conditionally defines the HAS_WCSXFRM symbol if the wcsxfrm() routine is available and can be used to compare wide character strings.

d_wctomb

From d_wctomb.U:

This variable conditionally defines the HAS_WCTOMB symbol, which indicates to the C program that the wctomb() routine is available to convert a wide character to a multibyte.

d_writev

From d_writev.U:

This variable conditionally defines the HAS_WRITEV symbol, which indicates to the C program that the writev() routine is available.

d_xenix

From Guess.U:

This variable conditionally defines the symbol XENIX, which alerts the C program that it runs under Xenix.

date

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the date program. After Configure runs, the value is reset to a plain date and is not useful.

db_hashtype

From i_db.U:

This variable contains the type of the hash structure element in the <db.h> header file. In older versions of DB, it was int, while in newer ones it is u_int32_t.

db_prefixtype

From i_db.U:

This variable contains the type of the prefix structure element in the <db.h> header file. In older versions of DB, it was int, while in newer ones it is size_t.

db_version_major

From i_db.U:

This variable contains the major version number of Berkeley DB found in the <db.h> header file.

db_version_minor

From i_db.U:

This variable contains the minor version number of Berkeley DB found in the <db.h> header file. For DB version 1 this is always 0.

db_version_patch

From i_db.U:

This variable contains the patch version number of Berkeley DB found in the <db.h> header file. For DB version 1 this is always 0.

default_inc_excludes_dot

From defaultincdot.U:

When defined, remove the legacy . from @INC

direntrytype

From i_dirent.U:

This symbol is set to struct direct or struct dirent depending on whether dirent is available or not. You should use this pseudo type to portably declare your directory entries.

dlext

From dlext.U:

This variable contains the extension that is to be used for the dynamically loaded modules that perl generates.

dlsrc

From dlsrc.U:

This variable contains the name of the dynamic loading file that will be used with the package.

doubleinfbytes

From infnan.U:

This variable contains comma-separated list of hexadecimal bytes for the double precision infinity.

doublekind

From longdblfio.U:

This variable, if defined, encodes the type of a double: 1 = IEEE 754 32-bit little endian, 2 = IEEE 754 32-bit big endian, 3 = IEEE 754 64-bit little endian, 4 = IEEE 754 64-bit big endian, 5 = IEEE 754 128-bit little endian, 6 = IEEE 754 128-bit big endian, 7 = IEEE 754 64-bit mixed endian le-be, 8 = IEEE 754 64-bit mixed endian be-le, 9 = VAX 32bit little endian F float format 10 = VAX 64bit little endian D float format 11 = VAX 64bit little endian G float format 12 = IBM 32bit format 13 = IBM 64bit format 14 = Cray 64bit format -1 = unknown format.

doublemantbits

From mantbits.U:

This symbol, if defined, tells how many mantissa bits there are in double precision floating point format. Note that this is usually DBL_MANT_DIG minus one, since with the standard IEEE 754 formats DBL_MANT_DIG includes the implicit bit which doesn't really exist.

doublenanbytes

From infnan.U:

This variable contains comma-separated list of hexadecimal bytes for the double precision not-a-number.

doublesize

From doublesize.U:

This variable contains the value of the DOUBLESIZE symbol, which indicates to the C program how many bytes there are in a double.

drand01

From randfunc.U:

Indicates the macro to be used to generate normalized random numbers. Uses randfunc, often divided by (double) (((unsigned long) 1 << randbits)) in order to normalize the result. In C programs, the macro Drand01 is mapped to drand01.

drand48_r_proto

From d_drand48_r.U:

This variable encodes the prototype of drand48_r. It is zero if d_drand48_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_drand48_r is defined.

dtrace

From usedtrace.U:

This variable holds the location of the dtrace executable.

dtraceobject

From dtraceobject.U:

Whether we need to build an object file with the dtrace tool.

dtracexnolibs

From dtraceobject.U:

Whether dtrace accepts -xnolibs. If available we call dtrace -h and dtrace -G with -xnolibs to allow dtrace to run in a jail on FreeBSD.

dynamic_ext

From Extensions.U:

This variable holds a list of XS extension files we want to link dynamically into the package. It is used by Makefile.

e

eagain

From nblock_io.U:

This variable bears the symbolic errno code set by read() when no data is present on the file and non-blocking I/O was enabled (otherwise, read() blocks naturally).

ebcdic

From ebcdic.U:

This variable conditionally defines EBCDIC if this system uses EBCDIC encoding.

echo

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the echo program. After Configure runs, the value is reset to a plain echo and is not useful.

egrep

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the egrep program. After Configure runs, the value is reset to a plain egrep and is not useful.

emacs

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

endgrent_r_proto

From d_endgrent_r.U:

This variable encodes the prototype of endgrent_r. It is zero if d_endgrent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endgrent_r is defined.

endhostent_r_proto

From d_endhostent_r.U:

This variable encodes the prototype of endhostent_r. It is zero if d_endhostent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endhostent_r is defined.

endnetent_r_proto

From d_endnetent_r.U:

This variable encodes the prototype of endnetent_r. It is zero if d_endnetent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endnetent_r is defined.

endprotoent_r_proto

From d_endprotoent_r.U:

This variable encodes the prototype of endprotoent_r. It is zero if d_endprotoent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endprotoent_r is defined.

endpwent_r_proto

From d_endpwent_r.U:

This variable encodes the prototype of endpwent_r. It is zero if d_endpwent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endpwent_r is defined.

endservent_r_proto

From d_endservent_r.U:

This variable encodes the prototype of endservent_r. It is zero if d_endservent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_endservent_r is defined.

eunicefix

From Init.U:

When running under Eunice this variable contains a command which will convert a shell script to the proper form of text file for it to be executable by the shell. On other systems it is a no-op.

exe_ext

From Unix.U:

This is an old synonym for _exe.

expr

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the expr program. After Configure runs, the value is reset to a plain expr and is not useful.

extensions

From Extensions.U:

This variable holds a list of all extension files (both XS and non-xs) installed with the package. It is propagated to Config.pm and is typically used to test whether a particular extension is available.

extern_C

From Csym.U:

ANSI C requires extern where C++ requires 'extern C'. This variable can be used in Configure to do the right thing.

extras

From Extras.U:

This variable holds a list of extra modules to install.

f

fflushNULL

From fflushall.U:

This symbol, if defined, tells that fflush(NULL) correctly flushes all pending stdio output without side effects. In particular, on some platforms calling fflush(NULL) *still* corrupts STDIN if it is a pipe.

fflushall

From fflushall.U:

This symbol, if defined, tells that to flush all pending stdio output one must loop through all the stdio file handles stored in an array and fflush them. Note that if fflushNULL is defined, fflushall will not even be probed for and will be left undefined.

find

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

firstmakefile

From Unix.U:

This variable defines the first file searched by make. On unix, it is makefile (then Makefile). On case-insensitive systems, it might be something else. This is only used to deal with convoluted make depend tricks.

flex

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

fpossize

From fpossize.U:

This variable contains the size of a fpostype in bytes.

fpostype

From fpostype.U:

This variable defines Fpos_t to be something like fpos_t, long, uint, or whatever type is used to declare file positions in libc.

freetype

From mallocsrc.U:

This variable contains the return type of free(). It is usually void, but occasionally int.

from

From Cross.U:

This variable contains the command used by Configure to copy files from the target host. Useful and available only during Perl build. The string : if not cross-compiling.

full_ar

From Loc_ar.U:

This variable contains the full pathname to ar, whether or not the user has specified portability. This is only used in the Makefile.SH.

full_csh

From d_csh.U:

This variable contains the full pathname to csh, whether or not the user has specified portability. This is only used in the compiled C program, and we assume that all systems which can share this executable will have the same full pathname to csh.

full_sed

From Loc_sed.U:

This variable contains the full pathname to sed, whether or not the user has specified portability. This is only used in the compiled C program, and we assume that all systems which can share this executable will have the same full pathname to sed.

g

gccansipedantic

From gccvers.U:

If GNU cc (gcc) is used, this variable will enable (if set) the -ansi and -pedantic ccflags for building core files (through cflags script). (See Porting/pumpkin.pod for full description).

gccosandvers

From gccvers.U:

If GNU cc (gcc) is used, this variable holds the operating system and version used to compile gcc. It is set to '' if not gcc, or if nothing useful can be parsed as the os version.

gccversion

From gccvers.U:

If GNU cc (gcc) is used, this variable holds 1 or 2 to indicate whether the compiler is version 1 or 2. This is used in setting some of the default cflags. It is set to '' if not gcc.

getgrent_r_proto

From d_getgrent_r.U:

This variable encodes the prototype of getgrent_r. It is zero if d_getgrent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getgrent_r is defined.

getgrgid_r_proto

From d_getgrgid_r.U:

This variable encodes the prototype of getgrgid_r. It is zero if d_getgrgid_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getgrgid_r is defined.

getgrnam_r_proto

From d_getgrnam_r.U:

This variable encodes the prototype of getgrnam_r. It is zero if d_getgrnam_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getgrnam_r is defined.

gethostbyaddr_r_proto

From d_gethostbyaddr_r.U:

This variable encodes the prototype of gethostbyaddr_r. It is zero if d_gethostbyaddr_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_gethostbyaddr_r is defined.

gethostbyname_r_proto

From d_gethostbyname_r.U:

This variable encodes the prototype of gethostbyname_r. It is zero if d_gethostbyname_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_gethostbyname_r is defined.

gethostent_r_proto

From d_gethostent_r.U:

This variable encodes the prototype of gethostent_r. It is zero if d_gethostent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_gethostent_r is defined.

getlogin_r_proto

From d_getlogin_r.U:

This variable encodes the prototype of getlogin_r. It is zero if d_getlogin_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getlogin_r is defined.

getnetbyaddr_r_proto

From d_getnetbyaddr_r.U:

This variable encodes the prototype of getnetbyaddr_r. It is zero if d_getnetbyaddr_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getnetbyaddr_r is defined.

getnetbyname_r_proto

From d_getnetbyname_r.U:

This variable encodes the prototype of getnetbyname_r. It is zero if d_getnetbyname_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getnetbyname_r is defined.

getnetent_r_proto

From d_getnetent_r.U:

This variable encodes the prototype of getnetent_r. It is zero if d_getnetent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getnetent_r is defined.

getprotobyname_r_proto

From d_getprotobyname_r.U:

This variable encodes the prototype of getprotobyname_r. It is zero if d_getprotobyname_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getprotobyname_r is defined.

getprotobynumber_r_proto

From d_getprotobynumber_r.U:

This variable encodes the prototype of getprotobynumber_r. It is zero if d_getprotobynumber_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getprotobynumber_r is defined.

getprotoent_r_proto

From d_getprotoent_r.U:

This variable encodes the prototype of getprotoent_r. It is zero if d_getprotoent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getprotoent_r is defined.

getpwent_r_proto

From d_getpwent_r.U:

This variable encodes the prototype of getpwent_r. It is zero if d_getpwent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getpwent_r is defined.

getpwnam_r_proto

From d_getpwnam_r.U:

This variable encodes the prototype of getpwnam_r. It is zero if d_getpwnam_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getpwnam_r is defined.

getpwuid_r_proto

From d_getpwuid_r.U:

This variable encodes the prototype of getpwuid_r. It is zero if d_getpwuid_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getpwuid_r is defined.

getservbyname_r_proto

From d_getservbyname_r.U:

This variable encodes the prototype of getservbyname_r. It is zero if d_getservbyname_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getservbyname_r is defined.

getservbyport_r_proto

From d_getservbyport_r.U:

This variable encodes the prototype of getservbyport_r. It is zero if d_getservbyport_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getservbyport_r is defined.

getservent_r_proto

From d_getservent_r.U:

This variable encodes the prototype of getservent_r. It is zero if d_getservent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getservent_r is defined.

getspnam_r_proto

From d_getspnam_r.U:

This variable encodes the prototype of getspnam_r. It is zero if d_getspnam_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_getspnam_r is defined.

gidformat

From gidf.U:

This variable contains the format string used for printing a Gid_t.

gidsign

From gidsign.U:

This variable contains the signedness of a gidtype. 1 for unsigned, -1 for signed.

gidsize

From gidsize.U:

This variable contains the size of a gidtype in bytes.

gidtype

From gidtype.U:

This variable defines Gid_t to be something like gid_t, int, ushort, or whatever type is used to declare the return type of getgid(). Typically, it is the type of group ids in the kernel.

glibpth

From libpth.U:

This variable holds the general path (space-separated) used to find libraries. It may contain directories that do not exist on this platform, libpth is the cleaned-up version.

gmake

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the gmake program. After Configure runs, the value is reset to a plain gmake and is not useful.

gmtime_r_proto

From d_gmtime_r.U:

This variable encodes the prototype of gmtime_r. It is zero if d_gmtime_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_gmtime_r is defined.

gnulibc_version

From d_gnulibc.U:

This variable contains the version number of the GNU C library. It is usually something like 2.2.5. It is a plain '' if this is not the GNU C library, or if the version is unknown.

grep

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the grep program. After Configure runs, the value is reset to a plain grep and is not useful.

groupcat

From nis.U:

This variable contains a command that produces the text of the /etc/group file. This is normally "cat /etc/group", but can be "ypcat group" when NIS is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

groupstype

From groupstype.U:

This variable defines Groups_t to be something like gid_t, int, ushort, or whatever type is used for the second argument to getgroups() and setgroups(). Usually, this is the same as gidtype (gid_t), but sometimes it isn't.

gzip

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the gzip program. After Configure runs, the value is reset to a plain gzip and is not useful.

h

h_fcntl

From h_fcntl.U:

This is variable gets set in various places to tell i_fcntl that <fcntl.h> should be included.

h_sysfile

From h_sysfile.U:

This is variable gets set in various places to tell i_sys_file that <sys/file.h> should be included.

hint

From Oldconfig.U:

Gives the type of hints used for previous answers. May be one of default, recommended or previous.

hostcat

From nis.U:

This variable contains a command that produces the text of the /etc/hosts file. This is normally "cat /etc/hosts", but can be "ypcat hosts" when NIS is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

hostgenerate

From Cross.U:

This variable contains the path to a generate_uudmap binary that can be run on the host OS when cross-compiling. Useful and available only during Perl build. Empty string '' if not cross-compiling.

hostosname

From Cross.U:

This variable contains the original value of $^O for hostperl when cross-compiling. This is useful to pick the proper tools when running build code in the host. Empty string '' if not cross-compiling.

hostperl

From Cross.U:

This variable contains the path to a miniperl binary that can be run on the host OS when cross-compiling. Useful and available only during Perl build. Empty string '' if not cross-compiling.

html1dir

From html1dir.U:

This variable contains the name of the directory in which html source pages are to be put. This directory is for pages that describe whole programs, not libraries or modules. It is intended to correspond roughly to section 1 of the Unix manuals.

html1direxp

From html1dir.U:

This variable is the same as the html1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

html3dir

From html3dir.U:

This variable contains the name of the directory in which html source pages are to be put. This directory is for pages that describe libraries or modules. It is intended to correspond roughly to section 3 of the Unix manuals.

html3direxp

From html3dir.U:

This variable is the same as the html3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

i

i16size

From perlxv.U:

This variable is the size of an I16 in bytes.

i16type

From perlxv.U:

This variable contains the C type used for Perl's I16.

i32dformat

From perlx32f.U:

This variable contains the format string used for printing a Perl I32 as a signed decimal integer.

i32size

From perlxv.U:

This variable is the size of an I32 in bytes.

i32type

From perlxv.U:

This variable contains the C type used for Perl's I32.

i64size

From perlxv.U:

This variable is the size of an I64 in bytes.

i64type

From perlxv.U:

This variable contains the C type used for Perl's I64.

i8size

From perlxv.U:

This variable is the size of an I8 in bytes.

i8type

From perlxv.U:

This variable contains the C type used for Perl's I8.

i_arpainet

From i_arpainet.U:

This variable conditionally defines the I_ARPA_INET symbol, and indicates whether a C program should include <arpa/inet.h>.

i_bfd

From i_bfd.U:

This variable conditionally defines the I_BFD symbol, and indicates whether a C program can include <bfd.h>.

i_bsdioctl

From i_sysioctl.U:

This variable conditionally defines the I_SYS_BSDIOCTL symbol, which indicates to the C program that <sys/bsdioctl.h> exists and should be included.

i_crypt

From i_crypt.U:

This variable conditionally defines the I_CRYPT symbol, and indicates whether a C program should include <crypt.h>.

i_db

From i_db.U:

This variable conditionally defines the I_DB symbol, and indicates whether a C program may include Berkeley's DB include file <db.h>.

i_dbm

From i_dbm.U:

This variable conditionally defines the I_DBM symbol, which indicates to the C program that <dbm.h> exists and should be included.

i_dirent

From i_dirent.U:

This variable conditionally defines I_DIRENT, which indicates to the C program that it should include <dirent.h>.

i_dlfcn

From i_dlfcn.U:

This variable conditionally defines the I_DLFCN symbol, which indicates to the C program that <dlfcn.h> exists and should be included.

i_execinfo

From i_execinfo.U:

This variable conditionally defines the I_EXECINFO symbol, and indicates whether a C program may include <execinfo.h>, for backtrace() support.

i_fcntl

From i_fcntl.U:

This variable controls the value of I_FCNTL (which tells the C program to include <fcntl.h>).

i_fenv

From i_fenv.U:

This variable conditionally defines the I_FENV symbol, which indicates to the C program that <fenv.h> exists and should be included.

i_fp

From i_fp.U:

This variable conditionally defines the I_FP symbol, and indicates whether a C program should include <fp.h>.

i_fp_class

From i_fp_class.U:

This variable conditionally defines the I_FP_CLASS symbol, and indicates whether a C program should include <fp_class.h>.

i_gdbm

From i_gdbm.U:

This variable conditionally defines the I_GDBM symbol, which indicates to the C program that <gdbm.h> exists and should be included.

i_gdbm_ndbm

From i_ndbm.U:

This variable conditionally defines the I_GDBM_NDBM symbol, which indicates to the C program that <gdbm-ndbm.h> exists and should be included. This is the location of the ndbm.h compatibility file in Debian 4.0.

i_gdbmndbm

From i_ndbm.U:

This variable conditionally defines the I_GDBMNDBM symbol, which indicates to the C program that <gdbm/ndbm.h> exists and should be included. This was the location of the ndbm.h compatibility file in RedHat 7.1.

i_grp

From i_grp.U:

This variable conditionally defines the I_GRP symbol, and indicates whether a C program should include <grp.h>.

i_ieeefp

From i_ieeefp.U:

This variable conditionally defines the I_IEEEFP symbol, and indicates whether a C program should include <ieeefp.h>.

i_inttypes

From i_inttypes.U:

This variable conditionally defines the I_INTTYPES symbol, and indicates whether a C program should include <inttypes.h>.

i_langinfo

From i_langinfo.U:

This variable conditionally defines the I_LANGINFO symbol, and indicates whether a C program should include <langinfo.h>.

i_libutil

From i_libutil.U:

This variable conditionally defines the I_LIBUTIL symbol, and indicates whether a C program should include <libutil.h>.

i_locale

From i_locale.U:

This variable conditionally defines the I_LOCALE symbol, and indicates whether a C program should include <locale.h>.

i_machcthr

From i_machcthr.U:

This variable conditionally defines the I_MACH_CTHREADS symbol, and indicates whether a C program should include <mach/cthreads.h>.

i_malloc

From i_malloc.U:

This variable conditionally defines the I_MALLOC symbol, and indicates whether a C program should include <malloc.h>.

i_mallocmalloc

From i_mallocmalloc.U:

This variable conditionally defines the I_MALLOCMALLOC symbol, and indicates whether a C program should include <malloc/malloc.h>.

i_mntent

From i_mntent.U:

This variable conditionally defines the I_MNTENT symbol, and indicates whether a C program should include <mntent.h>.

i_ndbm

From i_ndbm.U:

This variable conditionally defines the I_NDBM symbol, which indicates to the C program that <ndbm.h> exists and should be included.

i_netdb

From i_netdb.U:

This variable conditionally defines the I_NETDB symbol, and indicates whether a C program should include <netdb.h>.

i_neterrno

From i_neterrno.U:

This variable conditionally defines the I_NET_ERRNO symbol, which indicates to the C program that <net/errno.h> exists and should be included.

i_netinettcp

From i_netinettcp.U:

This variable conditionally defines the I_NETINET_TCP symbol, and indicates whether a C program should include <netinet/tcp.h>.

i_niin

From i_niin.U:

This variable conditionally defines I_NETINET_IN, which indicates to the C program that it should include <netinet/in.h>. Otherwise, you may try <sys/in.h>.

i_poll

From i_poll.U:

This variable conditionally defines the I_POLL symbol, and indicates whether a C program should include <poll.h>.

i_prot

From i_prot.U:

This variable conditionally defines the I_PROT symbol, and indicates whether a C program should include <prot.h>.

i_pthread

From i_pthread.U:

This variable conditionally defines the I_PTHREAD symbol, and indicates whether a C program should include <pthread.h>.

i_pwd

From i_pwd.U:

This variable conditionally defines I_PWD, which indicates to the C program that it should include <pwd.h>.

i_quadmath

From i_quadmath.U:

This variable conditionally defines I_QUADMATH, which indicates to the C program that it should include <quadmath.h>.

i_rpcsvcdbm

From i_dbm.U:

This variable conditionally defines the I_RPCSVC_DBM symbol, which indicates to the C program that <rpcsvc/dbm.h> exists and should be included. Some System V systems might need this instead of <dbm.h>.

i_sgtty

From i_termio.U:

This variable conditionally defines the I_SGTTY symbol, which indicates to the C program that it should include <sgtty.h> rather than <termio.h>.

i_shadow

From i_shadow.U:

This variable conditionally defines the I_SHADOW symbol, and indicates whether a C program should include <shadow.h>.

i_socks

From i_socks.U:

This variable conditionally defines the I_SOCKS symbol, and indicates whether a C program should include <socks.h>.

i_stdbool

From i_stdbool.U:

This variable conditionally defines the I_STDBOOL symbol, which indicates to the C program that <stdbool.h> exists and should be included.

i_stdint

From i_stdint.U:

This variable conditionally defines the I_STDINT symbol, which indicates to the C program that <stdint.h> exists and should be included.

i_stdlib

From i_stdlib.U:

This variable unconditionally defines the I_STDLIB symbol.

i_sunmath

From i_sunmath.U:

This variable conditionally defines the I_SUNMATH symbol, and indicates whether a C program should include <sunmath.h>.

i_sysaccess

From i_sysaccess.U:

This variable conditionally defines the I_SYS_ACCESS symbol, and indicates whether a C program should include <sys/access.h>.

i_sysdir

From i_sysdir.U:

This variable conditionally defines the I_SYS_DIR symbol, and indicates whether a C program should include <sys/dir.h>.

i_sysfile

From i_sysfile.U:

This variable conditionally defines the I_SYS_FILE symbol, and indicates whether a C program should include <sys/file.h> to get R_OK and friends.

i_sysfilio

From i_sysioctl.U:

This variable conditionally defines the I_SYS_FILIO symbol, which indicates to the C program that <sys/filio.h> exists and should be included in preference to <sys/ioctl.h>.

i_sysin

From i_niin.U:

This variable conditionally defines I_SYS_IN, which indicates to the C program that it should include <sys/in.h> instead of <netinet/in.h>.

i_sysioctl

From i_sysioctl.U:

This variable conditionally defines the I_SYS_IOCTL symbol, which indicates to the C program that <sys/ioctl.h> exists and should be included.

i_syslog

From i_syslog.U:

This variable conditionally defines the I_SYSLOG symbol, and indicates whether a C program should include <syslog.h>.

i_sysmman

From i_sysmman.U:

This variable conditionally defines the I_SYS_MMAN symbol, and indicates whether a C program should include <sys/mman.h>.

i_sysmode

From i_sysmode.U:

This variable conditionally defines the I_SYSMODE symbol, and indicates whether a C program should include <sys/mode.h>.

i_sysmount

From i_sysmount.U:

This variable conditionally defines the I_SYSMOUNT symbol, and indicates whether a C program should include <sys/mount.h>.

i_sysndir

From i_sysndir.U:

This variable conditionally defines the I_SYS_NDIR symbol, and indicates whether a C program should include <sys/ndir.h>.

i_sysparam

From i_sysparam.U:

This variable conditionally defines the I_SYS_PARAM symbol, and indicates whether a C program should include <sys/param.h>.

i_syspoll

From i_syspoll.U:

This variable conditionally defines the I_SYS_POLL symbol, which indicates to the C program that it should include <sys/poll.h>.

i_sysresrc

From i_sysresrc.U:

This variable conditionally defines the I_SYS_RESOURCE symbol, and indicates whether a C program should include <sys/resource.h>.

i_syssecrt

From i_syssecrt.U:

This variable conditionally defines the I_SYS_SECURITY symbol, and indicates whether a C program should include <sys/security.h>.

i_sysselct

From i_sysselct.U:

This variable conditionally defines I_SYS_SELECT, which indicates to the C program that it should include <sys/select.h> in order to get the definition of struct timeval.

i_syssockio

From i_sysioctl.U:

This variable conditionally defines I_SYS_SOCKIO to indicate to the C program that socket ioctl codes may be found in <sys/sockio.h> instead of <sys/ioctl.h>.

i_sysstat

From i_sysstat.U:

This variable conditionally defines the I_SYS_STAT symbol, and indicates whether a C program should include <sys/stat.h>.

i_sysstatfs

From i_sysstatfs.U:

This variable conditionally defines the I_SYSSTATFS symbol, and indicates whether a C program should include <sys/statfs.h>.

i_sysstatvfs

From i_sysstatvfs.U:

This variable conditionally defines the I_SYSSTATVFS symbol, and indicates whether a C program should include <sys/statvfs.h>.

i_syssyscall

From i_syssyscall.U:

This variable conditionally defines the I_SYS_SYSCALL symbol, and indicates whether a C program should include <sys/syscall.h>.

i_systime

From i_time.U:

This variable conditionally defines I_SYS_TIME, which indicates to the C program that it should include <sys/time.h>.

i_systimek

From i_time.U:

This variable conditionally defines I_SYS_TIME_KERNEL, which indicates to the C program that it should include <sys/time.h> with KERNEL defined.

i_systimes

From i_systimes.U:

This variable conditionally defines the I_SYS_TIMES symbol, and indicates whether a C program should include <sys/times.h>.

i_systypes

From i_systypes.U:

This variable conditionally defines the I_SYS_TYPES symbol, and indicates whether a C program should include <sys/types.h>.

i_sysuio

From i_sysuio.U:

This variable conditionally defines the I_SYSUIO symbol, and indicates whether a C program should include <sys/uio.h>.

i_sysun

From i_sysun.U:

This variable conditionally defines I_SYS_UN, which indicates to the C program that it should include <sys/un.h> to get UNIX domain socket definitions.

i_sysutsname

From i_sysutsname.U:

This variable conditionally defines the I_SYSUTSNAME symbol, and indicates whether a C program should include <sys/utsname.h>.

i_sysvfs

From i_sysvfs.U:

This variable conditionally defines the I_SYSVFS symbol, and indicates whether a C program should include <sys/vfs.h>.

i_syswait

From i_syswait.U:

This variable conditionally defines I_SYS_WAIT, which indicates to the C program that it should include <sys/wait.h>.

i_termio

From i_termio.U:

This variable conditionally defines the I_TERMIO symbol, which indicates to the C program that it should include <termio.h> rather than <sgtty.h>.

i_termios

From i_termio.U:

This variable conditionally defines the I_TERMIOS symbol, which indicates to the C program that the POSIX <termios.h> file is to be included.

i_time

From i_time.U:

This variable unconditionally defines I_TIME, which indicates to the C program that it should include <time.h>.

i_unistd

From i_unistd.U:

This variable conditionally defines the I_UNISTD symbol, and indicates whether a C program should include <unistd.h>.

i_ustat

From i_ustat.U:

This variable conditionally defines the I_USTAT symbol, and indicates whether a C program should include <ustat.h>.

i_utime

From i_utime.U:

This variable conditionally defines the I_UTIME symbol, and indicates whether a C program should include <utime.h>.

i_vfork

From i_vfork.U:

This variable conditionally defines the I_VFORK symbol, and indicates whether a C program should include vfork.h.

i_wchar

From i_wchar.U:

This variable conditionally defines the I_WCHAR symbol, that indicates whether a C program may include <wchar.h>.

i_wctype

From i_wctype.U:

This variable conditionally defines the I_WCTYPE symbol, that indicates whether a C program may include <wctype.h>.

i_xlocale

From d_newlocale.U:

This symbol, if defined, indicates to the C program that the header xlocale.h is available. See also xlocale_needed.

ignore_versioned_solibs

From libs.U:

This variable should be non-empty if non-versioned shared libraries (libfoo.so.x.y) are to be ignored (because they cannot be linked against).

inc_version_list

From inc_version_list.U:

This variable specifies the list of subdirectories in over which perl.c:incpush() and lib/lib.pm will automatically search when adding directories to @INC. The elements in the list are separated by spaces. This is only useful if you have a perl library directory tree structured like the default one. See INSTALL for how this works. The versioned site_perl directory was introduced in 5.005, so that is the lowest possible value.

This list includes architecture-dependent directories back to version $api_versionstring (e.g. 5.5.640) and architecture-independent directories all the way back to 5.005.

inc_version_list_init

From inc_version_list.U:

This variable holds the same list as inc_version_list, but each item is enclosed in double quotes and separated by commas, suitable for use in the PERL_INC_VERSION_LIST initialization.

incpath

From usrinc.U:

This variable must precede the normal include path to get the right one, as in $incpath/usr/include or $incpath/usr/lib. Value can be "" or /bsd43 on mips.

incpth

From libpth.U:

This variable must precede the normal include path to get the right one, as in $incpath/usr/include or $incpath/usr/lib. Value can be "" or /bsd43 on mips.

inews

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

initialinstalllocation

From bin.U:

When userelocatableinc is true, this variable holds the location that make install should copy the perl binary to, with all the run-time relocatable paths calculated from this at install time. When used, it is initialized to the original value of binexp, and then binexp is set to .../, as the other binaries are found relative to the perl binary.

installarchlib

From archlib.U:

This variable is really the same as archlibexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installbin

From bin.U:

This variable is the same as binexp unless AFS is running in which case the user is explicitly prompted for it. This variable should always be used in your makefiles for maximum portability.

installhtml1dir

From html1dir.U:

This variable is really the same as html1direxp, unless you are using a different installprefix. For extra portability, you should only use this variable within your makefiles.

installhtml3dir

From html3dir.U:

This variable is really the same as html3direxp, unless you are using a different installprefix. For extra portability, you should only use this variable within your makefiles.

installman1dir

From man1dir.U:

This variable is really the same as man1direxp, unless you are using AFS in which case it points to the read/write location whereas man1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installman3dir

From man3dir.U:

This variable is really the same as man3direxp, unless you are using AFS in which case it points to the read/write location whereas man3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installprefix

From installprefix.U:

This variable holds the name of the directory below which "make install" will install the package. For most users, this is the same as prefix. However, it is useful for installing the software into a different (usually temporary) location after which it can be bundled up and moved somehow to the final location specified by prefix.

installprefixexp

From installprefix.U:

This variable holds the full absolute path of installprefix with all ~-expansion done.

installprivlib

From privlib.U:

This variable is really the same as privlibexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installscript

From scriptdir.U:

This variable is usually the same as scriptdirexp, unless you are on a system running AFS, in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installsitearch

From sitearch.U:

This variable is really the same as sitearchexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installsitebin

From sitebin.U:

This variable is usually the same as sitebinexp, unless you are on a system running AFS, in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installsitehtml1dir

From sitehtml1dir.U:

This variable is really the same as sitehtml1direxp, unless you are using AFS in which case it points to the read/write location whereas html1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitehtml3dir

From sitehtml3dir.U:

This variable is really the same as sitehtml3direxp, unless you are using AFS in which case it points to the read/write location whereas html3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitelib

From sitelib.U:

This variable is really the same as sitelibexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installsiteman1dir

From siteman1dir.U:

This variable is really the same as siteman1direxp, unless you are using AFS in which case it points to the read/write location whereas man1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsiteman3dir

From siteman3dir.U:

This variable is really the same as siteman3direxp, unless you are using AFS in which case it points to the read/write location whereas man3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitescript

From sitescript.U:

This variable is usually the same as sitescriptexp, unless you are on a system running AFS, in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installstyle

From installstyle.U:

This variable describes the style of the perl installation. This is intended to be useful for tools that need to manipulate entire perl distributions. Perl itself doesn't use this to find its libraries -- the library directories are stored directly in Config.pm. Currently, there are only two styles: lib and lib/perl5. The default library locations (e.g. privlib, sitelib) are either $prefix/lib or $prefix/lib/perl5. The former is useful if $prefix is a directory dedicated to perl (e.g. /opt/perl), while the latter is useful if $prefix is shared by many packages, e.g. if $prefix=/usr/local.

Unfortunately, while this style variable is used to set defaults for all three directory hierarchies (core, vendor, and site), there is no guarantee that the same style is actually appropriate for all those directories. For example, $prefix might be /opt/perl, but $siteprefix might be /usr/local. (Perhaps, in retrospect, the lib style should never have been supported, but it did seem like a nice idea at the time.)

The situation is even less clear for tools such as MakeMaker that can be used to install additional modules into non-standard places. For example, if a user intends to install a module into a private directory (perhaps by setting PREFIX on the Makefile.PL command line), then there is no reason to assume that the Configure-time $installstyle setting will be relevant for that PREFIX.

This may later be extended to include other information, so be careful with pattern-matching on the results.

For compatibility with perl5.005 and earlier, the default setting is based on whether or not $prefix contains the string perl.

installusrbinperl

From instubperl.U:

This variable tells whether Perl should be installed also as /usr/bin/perl in addition to $installbin/perl

installvendorarch

From vendorarch.U:

This variable is really the same as vendorarchexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorbin

From vendorbin.U:

This variable is really the same as vendorbinexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorhtml1dir

From vendorhtml1dir.U:

This variable is really the same as vendorhtml1direxp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorhtml3dir

From vendorhtml3dir.U:

This variable is really the same as vendorhtml3direxp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorlib

From vendorlib.U:

This variable is really the same as vendorlibexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorman1dir

From vendorman1dir.U:

This variable is really the same as vendorman1direxp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorman3dir

From vendorman3dir.U:

This variable is really the same as vendorman3direxp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

installvendorscript

From vendorscript.U:

This variable is really the same as vendorscriptexp but may differ on those systems using AFS. For extra portability, only this variable should be used in makefiles.

intsize

From intsize.U:

This variable contains the value of the INTSIZE symbol, which indicates to the C program how many bytes there are in an int.

From issymlink.U:

This variable holds the test command to test for a symbolic link (if they are supported). Typical values include test -h and test -L.

ivdformat

From perlxvf.U:

This variable contains the format string used for printing a Perl IV as a signed decimal integer.

ivsize

From perlxv.U:

This variable is the size of an IV in bytes.

ivtype

From perlxv.U:

This variable contains the C type used for Perl's IV.

k

known_extensions

From Extensions.U:

This variable holds a list of all extensions (both XS and non-xs) included in the package source distribution. This information is only really of use during the Perl build, as the list makes no distinction between extensions which were build and installed, and those which where not. See extensions for the list of extensions actually built and available.

ksh

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

l

ld

From dlsrc.U:

This variable indicates the program to be used to link libraries for dynamic loading. On some systems, it is ld. On ELF systems, it should be $cc. Mostly, we'll try to respect the hint file setting.

ld_can_script

From dlsrc.U:

This variable shows if the loader accepts scripts in the form of -Wl,--version-script=ld.script. This is currently only supported for GNU ld on ELF in dynamic loading builds.

lddlflags

From dlsrc.U:

This variable contains any special flags that might need to be passed to $ld to create a shared library suitable for dynamic loading. It is up to the makefile to use it. For hpux, it should be -b. For sunos 4.1, it is empty.

ldflags

From ccflags.U:

This variable contains any additional C loader flags desired by the user. It is up to the Makefile to use this.

ldflags_uselargefiles

From uselfs.U:

This variable contains the loader flags needed by large file builds and added to ldflags by hints files.

ldlibpthname

From libperl.U:

This variable holds the name of the shared library search path, often LD_LIBRARY_PATH. To get an empty string, the hints file must set this to none.

less

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the less program. After Configure runs, the value is reset to a plain less and is not useful.

lib_ext

From Unix.U:

This is an old synonym for _a.

libc

From libc.U:

This variable contains the location of the C library.

libperl

From libperl.U:

The perl executable is obtained by linking perlmain.c with libperl, any static extensions (usually just DynaLoader), and any other libraries needed on this system. libperl is usually libperl.a, but can also be libperl.so.xxx if the user wishes to build a perl executable with a shared library.

libpth

From libpth.U:

This variable holds the general path (space-separated) used to find libraries. It is intended to be used by other units.

libs

From libs.U:

This variable holds the additional libraries we want to use. It is up to the Makefile to deal with it. The list can be empty.

libsdirs

From libs.U:

This variable holds the directory names aka dirnames of the libraries we found and accepted, duplicates are removed.

libsfiles

From libs.U:

This variable holds the filenames aka basenames of the libraries we found and accepted.

libsfound

From libs.U:

This variable holds the full pathnames of the libraries we found and accepted.

libspath

From libs.U:

This variable holds the directory names probed for libraries.

libswanted

From Myinit.U:

This variable holds a list of all the libraries we want to search. The order is chosen to pick up the c library ahead of ucb or bsd libraries for SVR4.

libswanted_uselargefiles

From uselfs.U:

This variable contains the libraries needed by large file builds and added to ldflags by hints files. It is a space separated list of the library names without the lib prefix or any suffix, just like libswanted..

line

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lint

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lkflags

From ccflags.U:

This variable contains any additional C partial linker flags desired by the user. It is up to the Makefile to use this.

ln

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ln program. After Configure runs, the value is reset to a plain ln and is not useful.

lns

From lns.U:

This variable holds the name of the command to make symbolic links (if they are supported). It can be used in the Makefile. It is either ln -s or ln

localtime_r_proto

From d_localtime_r.U:

This variable encodes the prototype of localtime_r. It is zero if d_localtime_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_localtime_r is defined.

locincpth

From ccflags.U:

This variable contains a list of additional directories to be searched by the compiler. The appropriate -I directives will be added to ccflags. This is intended to simplify setting local directories from the Configure command line. It's not much, but it parallels the loclibpth stuff in libpth.U.

loclibpth

From libpth.U:

This variable holds the paths (space-separated) used to find local libraries. It is prepended to libpth, and is intended to be easily set from the command line.

longdblinfbytes

From infnan.U:

This variable contains comma-separated list of hexadecimal bytes for the long double precision infinity.

longdblkind

From d_longdbl.U:

This variable, if defined, encodes the type of a long double: 0 = double, 1 = IEEE 754 128-bit little endian, 2 = IEEE 754 128-bit big endian, 3 = x86 80-bit little endian, 4 = x86 80-bit big endian, 5 = double-double 128-bit little endian, 6 = double-double 128-bit big endian, 7 = 128-bit mixed-endian double-double (64-bit LEs in BE), 8 = 128-bit mixed-endian double-double (64-bit BEs in LE), 9 = 128-bit PDP-style mixed-endian long doubles, -1 = unknown format.

longdblmantbits

From mantbits.U:

This symbol, if defined, tells how many mantissa bits there are in long double precision floating point format. Note that this can be LDBL_MANT_DIG minus one, since LDBL_MANT_DIG can include the IEEE 754 implicit bit. The common x86-style 80-bit long double does not have an implicit bit.

longdblnanbytes

From infnan.U:

This variable contains comma-separated list of hexadecimal bytes for the long double precision not-a-number.

longdblsize

From d_longdbl.U:

This variable contains the value of the LONG_DOUBLESIZE symbol, which indicates to the C program how many bytes there are in a long double, if this system supports long doubles. Note that this is sizeof(long double), which may include unused bytes.

longlongsize

From d_longlong.U:

This variable contains the value of the LONGLONGSIZE symbol, which indicates to the C program how many bytes there are in a long long, if this system supports long long.

longsize

From intsize.U:

This variable contains the value of the LONGSIZE symbol, which indicates to the C program how many bytes there are in a long.

lp

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lpr

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

ls

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ls program. After Configure runs, the value is reset to a plain ls and is not useful.

lseeksize

From lseektype.U:

This variable defines lseektype to be something like off_t, long, or whatever type is used to declare lseek offset's type in the kernel (which also appears to be lseek's return type).

lseektype

From lseektype.U:

This variable defines lseektype to be something like off_t, long, or whatever type is used to declare lseek offset's type in the kernel (which also appears to be lseek's return type).

m

mail

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

mailx

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

make

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the make program. After Configure runs, the value is reset to a plain make and is not useful.

make_set_make

From make.U:

Some versions of make set the variable MAKE. Others do not. This variable contains the string to be included in Makefile.SH so that MAKE is set if needed, and not if not needed. Possible values are:

make_set_make=# # If your make program handles this for you,

make_set_make=MAKE=$make # if it doesn't.

This uses a comment character so that we can distinguish a set value (from a previous config.sh or Configure -D option) from an uncomputed value.

mallocobj

From mallocsrc.U:

This variable contains the name of the malloc.o that this package generates, if that malloc.o is preferred over the system malloc. Otherwise the value is null. This variable is intended for generating Makefiles. See mallocsrc.

mallocsrc

From mallocsrc.U:

This variable contains the name of the malloc.c that comes with the package, if that malloc.c is preferred over the system malloc. Otherwise the value is null. This variable is intended for generating Makefiles.

malloctype

From mallocsrc.U:

This variable contains the kind of ptr returned by malloc and realloc.

man1dir

From man1dir.U:

This variable contains the name of the directory in which manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself.

man1direxp

From man1dir.U:

This variable is the same as the man1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

man1ext

From man1dir.U:

This variable contains the extension that the manual page should have: one of n, l, or 1. The Makefile must supply the .. See man1dir.

man3dir

From man3dir.U:

This variable contains the name of the directory in which manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself.

man3direxp

From man3dir.U:

This variable is the same as the man3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

man3ext

From man3dir.U:

This variable contains the extension that the manual page should have: one of n, l, or 3. The Makefile must supply the .. See man3dir.

mips_type

From usrinc.U:

This variable holds the environment type for the mips system. Possible values are "BSD 4.3" and "System V".

mistrustnm

From Csym.U:

This variable can be used to establish a fallthrough for the cases where nm fails to find a symbol. If usenm is false or usenm is true and mistrustnm is false, this variable has no effect. If usenm is true and mistrustnm is compile, a test program will be compiled to try to find any symbol that can't be located via nm lookup. If mistrustnm is run, the test program will be run as well as being compiled.

mkdir

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the mkdir program. After Configure runs, the value is reset to a plain mkdir and is not useful.

mmaptype

From d_mmap.U:

This symbol contains the type of pointer returned by mmap() (and simultaneously the type of the first argument). It can be void * or caddr_t.

modetype

From modetype.U:

This variable defines modetype to be something like mode_t, int, unsigned short, or whatever type is used to declare file modes for system calls.

more

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the more program. After Configure runs, the value is reset to a plain more and is not useful.

multiarch

From multiarch.U:

This variable conditionally defines the MULTIARCH symbol which signifies the presence of multiplatform files. This is normally set by hints files.

mv

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

myarchname

From archname.U:

This variable holds the architecture name computed by Configure in a previous run. It is not intended to be perused by any user and should never be set in a hint file.

mydomain

From myhostname.U:

This variable contains the eventual value of the MYDOMAIN symbol, which is the domain of the host the program is going to run on. The domain must be appended to myhostname to form a complete host name. The dot comes with mydomain, and need not be supplied by the program.

myhostname

From myhostname.U:

This variable contains the eventual value of the MYHOSTNAME symbol, which is the name of the host the program is going to run on. The domain is not kept with hostname, but must be gotten from mydomain. The dot comes with mydomain, and need not be supplied by the program.

myuname

From Oldconfig.U:

The output of uname -a if available, otherwise the hostname. The whole thing is then lower-cased and slashes and single quotes are removed.

n

n

From n.U:

This variable contains the -n flag if that is what causes the echo command to suppress newline. Otherwise it is null. Correct usage is $echo $n "prompt for a question: $c".

need_va_copy

From need_va_copy.U:

This symbol, if defined, indicates that the system stores the variable argument list datatype, va_list, in a format that cannot be copied by simple assignment, so that some other means must be used when copying is required. As such systems vary in their provision (or non-provision) of copying mechanisms, handy.h defines a platform- independent macro, Perl_va_copy(src, dst), to do the job.

netdb_hlen_type

From netdbtype.U:

This variable holds the type used for the 2nd argument to gethostbyaddr(). Usually, this is int or size_t or unsigned. This is only useful if you have gethostbyaddr(), naturally.

netdb_host_type

From netdbtype.U:

This variable holds the type used for the 1st argument to gethostbyaddr(). Usually, this is char * or void *, possibly with or without a const prefix. This is only useful if you have gethostbyaddr(), naturally.

netdb_name_type

From netdbtype.U:

This variable holds the type used for the argument to gethostbyname(). Usually, this is char * or const char *. This is only useful if you have gethostbyname(), naturally.

netdb_net_type

From netdbtype.U:

This variable holds the type used for the 1st argument to getnetbyaddr(). Usually, this is int or long. This is only useful if you have getnetbyaddr(), naturally.

nm

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the nm program. After Configure runs, the value is reset to a plain nm and is not useful.

nm_opt

From usenm.U:

This variable holds the options that may be necessary for nm.

nm_so_opt

From usenm.U:

This variable holds the options that may be necessary for nm to work on a shared library but that can not be used on an archive library. Currently, this is only used by Linux, where nm --dynamic is *required* to get symbols from an ELF library which has been stripped, but nm --dynamic is *fatal* on an archive library. Maybe Linux should just always set usenm=false.

nonxs_ext

From Extensions.U:

This variable holds a list of all non-xs extensions built and installed by the package. By default, all non-xs extensions distributed will be built, with the exception of platform-specific extensions (currently only one VMS specific extension).

nroff

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the nroff program. After Configure runs, the value is reset to a plain nroff and is not useful.

nvEUformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %E-ish floating point format.

nvFUformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %F-ish floating point format.

nvGUformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %G-ish floating point format.

nv_overflows_integers_at

From perlxv.U:

This variable gives the largest integer value that NVs can hold as a constant floating point expression. If it could not be determined, it holds the value 0.

nv_preserves_uv_bits

From perlxv.U:

This variable indicates how many of bits type uvtype a variable nvtype can preserve.

nveformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %e-ish floating point format.

nvfformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %f-ish floating point format.

nvgformat

From perlxvf.U:

This variable contains the format string used for printing a Perl NV using %g-ish floating point format.

nvmantbits

From mantbits.U:

This variable tells how many bits the mantissa of a Perl NV has, not including the possible implicit bit.

nvsize

From perlxv.U:

This variable is the size of a Perl NV in bytes. Note that some floating point formats have unused bytes.

nvtype

From perlxv.U:

This variable contains the C type used for Perl's NV.

o

o_nonblock

From nblock_io.U:

This variable bears the symbol value to be used during open() or fcntl() to turn on non-blocking I/O for a file descriptor. If you wish to switch between blocking and non-blocking, you may try ioctl(FIOSNBIO) instead, but that is only supported by some devices.

obj_ext

From Unix.U:

This is an old synonym for _o.

old_pthread_create_joinable

From d_pthrattrj.U:

This variable defines the constant to use for creating joinable (aka undetached) pthreads. Unused if pthread.h defines PTHREAD_CREATE_JOINABLE. If used, possible values are PTHREAD_CREATE_UNDETACHED and __UNDETACHED.

optimize

From ccflags.U:

This variable contains any optimizer/debugger flag that should be used. It is up to the Makefile to use it.

orderlib

From orderlib.U:

This variable is true if the components of libraries must be ordered (with `lorder $* | tsort`) before placing them in an archive. Set to false if ranlib or ar can generate random libraries.

osname

From Oldconfig.U:

This variable contains the operating system name (e.g. sunos, solaris, hpux, etc.). It can be useful later on for setting defaults. Any spaces are replaced with underscores. It is set to a null string if we can't figure it out.

osvers

From Oldconfig.U:

This variable contains the operating system version (e.g. 4.1.3, 5.2, etc.). It is primarily used for helping select an appropriate hints file, but might be useful elsewhere for setting defaults. It is set to '' if we can't figure it out. We try to be flexible about how much of the version number to keep, e.g. if 4.1.1, 4.1.2, and 4.1.3 are essentially the same for this package, hints files might just be os_4.0 or os_4.1, etc., not keeping separate files for each little release.

otherlibdirs

From otherlibdirs.U:

This variable contains a colon-separated set of paths for the perl binary to search for additional library files or modules. These directories will be tacked to the end of @INC. Perl will automatically search below each path for version- and architecture-specific directories. See inc_version_list for more details. A value of means none and is used to preserve this value for the next run through Configure.

p

package

From package.U:

This variable contains the name of the package being constructed. It is primarily intended for the use of later Configure units.

pager

From pager.U:

This variable contains the name of the preferred pager on the system. Usual values are (the full pathnames of) more, less, pg, or cat.

passcat

From nis.U:

This variable contains a command that produces the text of the /etc/passwd file. This is normally "cat /etc/passwd", but can be "ypcat passwd" when NIS is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

patchlevel

From patchlevel.U:

The patchlevel level of this package. The value of patchlevel comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 6. In patchlevel.h, this is referred to as PERL_VERSION.

path_sep

From Unix.U:

This is an old synonym for p_ in Head.U, the character used to separate elements in the command shell search PATH.

perl

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the perl program. After Configure runs, the value is reset to a plain perl and is not useful.

perl5

From perl5.U:

This variable contains the full path (if any) to a previously installed perl5.005 or later suitable for running the script to determine inc_version_list.

perl_lc_all_category_positions_init

From disparate_lc_all.U:

This symbol, when defined, gives the C initializer for an array whose element [0] is the first category in the string returned by setlocale(LC_ALL, NULL) when not all categories are the same, on systems that use a positional notation. After element [0] is $lc_all_separator_init, then the category given by element [1], and so on.

perl_lc_all_separator

From disparate_lc_all.U:

This symbol, when defined, gives the substring used to separate categories in the aggregated string returned by setlocale(LC_ALL, NULL) when not all categories are in the same locale. This is for systems that use a positional notation as opposed to name=value pairs.

perl_patchlevel

From patchlevel.U:

This is the Perl patch level, a numeric change identifier, as defined by whichever source code maintenance system is used to maintain the patches; currently Perforce. It does not correlate with the Perl version numbers or the maintenance versus development dichotomy except by also being increasing.

perl_static_inline

From d_static_inline.U:

This variable defines the PERL_STATIC_INLINE symbol to the best-guess incantation to use for static inline functions. Possibilities include static inline (c99) static __inline__ (gcc -ansi) static __inline (MSVC) static _inline (older MSVC) static (c89 compilers)

perl_thread_local

From d_thread_local.U:

This variable gives the value for the PERL_THREAD_LOCAL symbol (when defined), which gives a linkage specification for thread-local storage.

perladmin

From perladmin.U:

Electronic mail address of the perl5 administrator.

perllibs

From End.U:

The list of libraries needed by Perl only (any libraries needed by extensions only will by dropped, if using dynamic loading).

perlpath

From perlpath.U:

This variable contains the eventual value of the PERLPATH symbol, which contains the name of the perl interpreter to be used in shell scripts and in the "eval exec" idiom. This variable is not necessarily the pathname of the file containing the perl interpreter; you must append the executable extension (_exe) if it is not already present. Note that Perl code that runs during the Perl build process cannot reference this variable, as Perl may not have been installed, or even if installed, may be a different version of Perl.

pg

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the pg program. After Configure runs, the value is reset to a plain pg and is not useful.

phostname

From myhostname.U:

This variable contains the eventual value of the PHOSTNAME symbol, which is a command that can be fed to popen() to get the host name. The program should probably not presume that the domain is or isn't there already.

pidtype

From pidtype.U:

This variable defines PIDTYPE to be something like pid_t, int, ushort, or whatever type is used to declare process ids in the kernel.

plibpth

From libpth.U:

Holds the private path used by Configure to find out the libraries. Its value is prepend to libpth. This variable takes care of special machines, like the mips. Usually, it should be empty.

pmake

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

pr

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

prefix

From prefix.U:

This variable holds the name of the directory below which the user will install the package. Usually, this is /usr/local, and executables go in /usr/local/bin, library stuff in /usr/local/lib, man pages in /usr/local/man, etc. It is only used to set defaults for things in bin.U, mansrc.U, privlib.U, or scriptdir.U.

prefixexp

From prefix.U:

This variable holds the full absolute path of the directory below which the user will install the package. Derived from prefix.

privlib

From privlib.U:

This variable contains the eventual value of the PRIVLIB symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution).

privlibexp

From privlib.U:

This variable is the ~name expanded version of privlib, so that you may use it directly in Makefiles or shell scripts.

procselfexe

From d_procselfexe.U:

If d_procselfexe is defined, $procselfexe is the filename of the symbolic link pointing to the absolute pathname of the executing program.

ptrsize

From ptrsize.U:

This variable contains the value of the PTRSIZE symbol, which indicates to the C program how many bytes there are in a pointer.

q

quadkind

From quadtype.U:

This variable, if defined, encodes the type of a quad: 1 = int, 2 = long, 3 = long long, 4 = int64_t.

quadtype

From quadtype.U:

This variable defines Quad_t to be something like long, int, long long, int64_t, or whatever type is used for 64-bit integers.

r

randbits

From randfunc.U:

Indicates how many bits are produced by the function used to generate normalized random numbers.

randfunc

From randfunc.U:

Indicates the name of the random number function to use. Values include drand48, random, and rand. In C programs, the Drand01 macro is defined to generate uniformly distributed random numbers over the range [0., 1.[ (see drand01 and nrand).

random_r_proto

From d_random_r.U:

This variable encodes the prototype of random_r. It is zero if d_random_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_random_r is defined.

randseedtype

From randfunc.U:

Indicates the type of the argument of the seedfunc.

ranlib

From orderlib.U:

This variable is set to the pathname of the ranlib program, if it is needed to generate random libraries. Set to : if ar can generate random libraries or if random libraries are not supported

rd_nodata

From nblock_io.U:

This variable holds the return code from read() when no data is present. It should be -1, but some systems return 0 when O_NDELAY is used, which is a shame because you cannot make the difference between no data and an EOF.. Sigh!

readdir64_r_proto

From d_readdir64_r.U:

This variable encodes the prototype of readdir64_r. It is zero if d_readdir64_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_readdir64_r is defined.

readdir_r_proto

From d_readdir_r.U:

This variable encodes the prototype of readdir_r. It is zero if d_readdir_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_readdir_r is defined.

revision

From patchlevel.U:

The value of revision comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 5. In patchlevel.h, this is referred to as PERL_REVISION.

rm

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the rm program. After Configure runs, the value is reset to a plain rm and is not useful.

rm_try

From Unix.U:

This is a cleanup variable for try test programs. Internal Configure use only.

rmail

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

run

From Cross.U:

This variable contains the command used by Configure to copy and execute a cross-compiled executable in the target host. Useful and available only during Perl build. Empty string '' if not cross-compiling.

runnm

From usenm.U:

This variable contains true or false depending whether the nm extraction should be performed or not, according to the value of usenm and the flags on the Configure command line.

s

sGMTIME_max

From time_size.U:

This variable defines the maximum value of the time_t offset that the system function gmtime () accepts

sGMTIME_min

From time_size.U:

This variable defines the minimum value of the time_t offset that the system function gmtime () accepts

sLOCALTIME_max

From time_size.U:

This variable defines the maximum value of the time_t offset that the system function localtime () accepts

sLOCALTIME_min

From time_size.U:

This variable defines the minimum value of the time_t offset that the system function localtime () accepts

sPRIEUldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format E) for output. The U in the name is to separate this from sPRIeldbl so that even case-blind systems can see the difference.

sPRIFUldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format F) for output. The U in the name is to separate this from sPRIfldbl so that even case-blind systems can see the difference.

sPRIGUldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format G) for output. The U in the name is to separate this from sPRIgldbl so that even case-blind systems can see the difference.

sPRIXU64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit hExADECimAl numbers (format X) for output. The U in the name is to separate this from sPRIx64 so that even case-blind systems can see the difference.

sPRId64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit decimal numbers (format d) for output.

sPRIeldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format e) for output.

sPRIfldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format f) for output.

sPRIgldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format g) for output.

sPRIi64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit decimal numbers (format i) for output.

sPRIo64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit octal numbers (format o) for output.

sPRIu64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit unsigned decimal numbers (format u) for output.

sPRIx64

From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit hexadecimal numbers (format x) for output.

sSCNfldbl

From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format f) for input.

sched_yield

From d_pthread_y.U:

This variable defines the way to yield the execution of the current thread.

scriptdir

From scriptdir.U:

This variable holds the name of the directory in which the user wants to put publicly scripts for the package in question. It is either the same directory as for binaries, or a special one that can be mounted across different architectures, like /usr/share. Programs must be prepared to deal with ~name expansion.

scriptdirexp

From scriptdir.U:

This variable is the same as scriptdir, but is filename expanded at configuration time, for programs not wanting to bother with it.

sed

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the sed program. After Configure runs, the value is reset to a plain sed and is not useful.

seedfunc

From randfunc.U:

Indicates the random number generating seed function. Values include srand48, srandom, and srand.

selectminbits

From selectminbits.U:

This variable holds the minimum number of bits operated by select. That is, if you do select(n, ...), how many bits at least will be cleared in the masks if some activity is detected. Usually this is either n or 32*ceil(n/32), especially many little-endians do the latter. This is only useful if you have select(), naturally.

selecttype

From selecttype.U:

This variable holds the type used for the 2nd, 3rd, and 4th arguments to select. Usually, this is fd_set *, if HAS_FD_SET is defined, and int * otherwise. This is only useful if you have select(), naturally.

sendmail

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

setgrent_r_proto

From d_setgrent_r.U:

This variable encodes the prototype of setgrent_r. It is zero if d_setgrent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setgrent_r is defined.

sethostent_r_proto

From d_sethostent_r.U:

This variable encodes the prototype of sethostent_r. It is zero if d_sethostent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_sethostent_r is defined.

setlocale_r_proto

From d_setlocale_r.U:

This variable encodes the prototype of setlocale_r. It is zero if d_setlocale_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setlocale_r is defined.

setnetent_r_proto

From d_setnetent_r.U:

This variable encodes the prototype of setnetent_r. It is zero if d_setnetent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setnetent_r is defined.

setprotoent_r_proto

From d_setprotoent_r.U:

This variable encodes the prototype of setprotoent_r. It is zero if d_setprotoent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setprotoent_r is defined.

setpwent_r_proto

From d_setpwent_r.U:

This variable encodes the prototype of setpwent_r. It is zero if d_setpwent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setpwent_r is defined.

setservent_r_proto

From d_setservent_r.U:

This variable encodes the prototype of setservent_r. It is zero if d_setservent_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_setservent_r is defined.

sh

From sh.U:

This variable contains the full pathname of the shell used on this system to execute Bourne shell scripts. Usually, this will be /bin/sh, though it's possible that some systems will have /bin/ksh, /bin/pdksh, /bin/ash, /bin/bash, or even something such as D:/bin/sh.exe. This unit comes before Options.U, so you can't set sh with a -D option, though you can override this (and startsh) with -O -Dsh=/bin/whatever -Dstartsh=whatever

shar

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

sharpbang

From spitshell.U:

This variable contains the string #! if this system supports that construct.

shmattype

From d_shmat.U:

This symbol contains the type of pointer returned by shmat(). It can be void * or char *.

shortsize

From intsize.U:

This variable contains the value of the SHORTSIZE symbol which indicates to the C program how many bytes there are in a short.

shrpenv

From libperl.U:

If the user builds a shared libperl.so, then we need to tell the perl executable where it will be able to find the installed libperl.so. One way to do this on some systems is to set the environment variable LD_RUN_PATH to the directory that will be the final location of the shared libperl.so. The makefile can use this with something like $shrpenv $(CC) -o perl perlmain.o $libperl $libs Typical values are shrpenv="env LD_RUN_PATH=$archlibexp/CORE" or shrpenv='' See the main perl Makefile.SH for actual working usage.

Alternatively, we might be able to use a command line option such as -R $archlibexp/CORE (Solaris) or -Wl,-rpath $archlibexp/CORE (Linux).

shsharp

From spitshell.U:

This variable tells further Configure units whether your sh can handle # comments.

sig_count

From sig_name.U:

This variable holds a number larger than the largest valid signal number. This is usually the same as the NSIG macro.

sig_name

From sig_name.U:

This variable holds the signal names, space separated. The leading SIG in signal name is removed. A ZERO is prepended to the list. This is currently not used, sig_name_init is used instead.

sig_name_init

From sig_name.U:

This variable holds the signal names, enclosed in double quotes and separated by commas, suitable for use in the SIG_NAME definition below. A ZERO is prepended to the list, and the list is terminated with a plain 0. The leading SIG in signal names is removed. See sig_num.

sig_num

From sig_name.U:

This variable holds the signal numbers, space separated. A ZERO is prepended to the list (corresponding to the fake SIGZERO). Those numbers correspond to the value of the signal listed in the same place within the sig_name list. This is currently not used, sig_num_init is used instead.

sig_num_init

From sig_name.U:

This variable holds the signal numbers, enclosed in double quotes and separated by commas, suitable for use in the SIG_NUM definition below. A ZERO is prepended to the list, and the list is terminated with a plain 0.

sig_size

From sig_name.U:

This variable contains the number of elements of the sig_name and sig_num arrays.

signal_t

From d_voidsig.U:

This variable holds the type of the signal handler (void or int).

sitearch

From sitearch.U:

This variable contains the eventual value of the SITEARCH symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution). The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-dependent modules in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitearchexp

From sitearch.U:

This variable is the ~name expanded version of sitearch, so that you may use it directly in Makefiles or shell scripts.

sitebin

From sitebin.U:

This variable holds the name of the directory in which the user wants to put add-on publicly executable files for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local executables in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitebinexp

From sitebin.U:

This is the same as the sitebin variable, but is filename expanded at configuration time, for use in your makefiles.

sitehtml1dir

From sitehtml1dir.U:

This variable contains the name of the directory in which site-specific html source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local html pages in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitehtml1direxp

From sitehtml1dir.U:

This variable is the same as the sitehtml1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

sitehtml3dir

From sitehtml3dir.U:

This variable contains the name of the directory in which site-specific library html source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local library html pages in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitehtml3direxp

From sitehtml3dir.U:

This variable is the same as the sitehtml3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

sitelib

From sitelib.U:

This variable contains the eventual value of the SITELIB symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution). The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-independent modules in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitelib_stem

From sitelib.U:

This variable is $sitelibexp with any trailing version-specific component removed. The elements in inc_version_list (inc_version_list.U) can be tacked onto this variable to generate a list of directories to search.

sitelibexp

From sitelib.U:

This variable is the ~name expanded version of sitelib, so that you may use it directly in Makefiles or shell scripts.

siteman1dir

From siteman1dir.U:

This variable contains the name of the directory in which site-specific manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local man1 pages in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

siteman1direxp

From siteman1dir.U:

This variable is the same as the siteman1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

siteman3dir

From siteman3dir.U:

This variable contains the name of the directory in which site-specific library man source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local man3 pages in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

siteman3direxp

From siteman3dir.U:

This variable is the same as the siteman3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

siteprefix

From siteprefix.U:

This variable holds the full absolute path of the directory below which the user will install add-on packages. See INSTALL for usage and examples.

siteprefixexp

From siteprefix.U:

This variable holds the full absolute path of the directory below which the user will install add-on packages. Derived from siteprefix.

sitescript

From sitescript.U:

This variable holds the name of the directory in which the user wants to put add-on publicly executable files for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local scripts in this directory with MakeMaker Makefile.PL or equivalent. See INSTALL for details.

sitescriptexp

From sitescript.U:

This is the same as the sitescript variable, but is filename expanded at configuration time, for use in your makefiles.

sizesize

From sizesize.U:

This variable contains the size of a sizetype in bytes.

sizetype

From sizetype.U:

This variable defines sizetype to be something like size_t, unsigned long, or whatever type is used to declare length parameters for string functions.

sleep

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

smail

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

so

From so.U:

This variable holds the extension used to identify shared libraries (also known as shared objects) on the system. Usually set to so.

sockethdr

From d_socket.U:

This variable has any cpp -I flags needed for socket support.

socketlib

From d_socket.U:

This variable has the names of any libraries needed for socket support.

socksizetype

From socksizetype.U:

This variable holds the type used for the size argument for various socket calls like accept. Usual values include socklen_t, size_t, and int.

sort

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the sort program. After Configure runs, the value is reset to a plain sort and is not useful.

spackage

From package.U:

This variable contains the name of the package being constructed, with the first letter uppercased, i.e. suitable for starting sentences.

spitshell

From spitshell.U:

This variable contains the command necessary to spit out a runnable shell on this system. It is either cat or a grep -v for # comments.

srand48_r_proto

From d_srand48_r.U:

This variable encodes the prototype of srand48_r. It is zero if d_srand48_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_srand48_r is defined.

srandom_r_proto

From d_srandom_r.U:

This variable encodes the prototype of srandom_r. It is zero if d_srandom_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_srandom_r is defined.

src

From src.U:

This variable holds the (possibly relative) path of the package source. It is up to the Makefile to use this variable and set VPATH accordingly to find the sources remotely. Use $pkgsrc to have an absolute path.

ssizetype

From ssizetype.U:

This variable defines ssizetype to be something like ssize_t, long or int. It is used by functions that return a count of bytes or an error condition. It must be a signed type. We will pick a type such that sizeof(SSize_t) == sizeof(Size_t).

st_dev_sign

From st_dev_def.U:

This variable contains the signedness of struct stat's st_dev. 1 for unsigned, -1 for signed.

st_dev_size

From st_dev_def.U:

This variable contains the size of struct stat's st_dev in bytes.

st_ino_sign

From st_ino_def.U:

This variable contains the signedness of struct stat's st_ino. 1 for unsigned, -1 for signed.

st_ino_size

From st_ino_def.U:

This variable contains the size of struct stat's st_ino in bytes.

startperl

From startperl.U:

This variable contains the string to put on the front of a perl script to make sure (hopefully) that it runs with perl and not some shell. Of course, that leading line must be followed by the classical perl idiom: eval 'exec perl -S $0 ${1+$@}' if $running_under_some_shell; to guarantee perl startup should the shell execute the script. Note that this magic incantation is not understood by csh.

startsh

From startsh.U:

This variable contains the string to put on the front of a shell script to make sure (hopefully) that it runs with sh and not some other shell.

static_ext

From Extensions.U:

This variable holds a list of XS extension files we want to link statically into the package. It is used by Makefile.

stdchar

From stdchar.U:

This variable conditionally defines STDCHAR to be the type of char used in stdio.h. It has the values "unsigned char" or char.

stdio_base

From d_stdstdio.U:

This variable defines how, given a FILE pointer, fp, to access the _base field (or equivalent) of stdio.h's FILE structure. This will be used to define the macro FILE_base(fp).

stdio_bufsiz

From d_stdstdio.U:

This variable defines how, given a FILE pointer, fp, to determine the number of bytes store in the I/O buffer pointer to by the _base field (or equivalent) of stdio.h's FILE structure. This will be used to define the macro FILE_bufsiz(fp).

stdio_cnt

From d_stdstdio.U:

This variable defines how, given a FILE pointer, fp, to access the _cnt field (or equivalent) of stdio.h's FILE structure. This will be used to define the macro FILE_cnt(fp).

stdio_filbuf

From d_stdstdio.U:

This variable defines how, given a FILE pointer, fp, to tell stdio to refill its internal buffers (?). This will be used to define the macro FILE_filbuf(fp).

stdio_ptr

From d_stdstdio.U:

This variable defines how, given a FILE pointer, fp, to access the _ptr field (or equivalent) of stdio.h's FILE structure. This will be used to define the macro FILE_ptr(fp).

stdio_stream_array

From stdio_streams.U:

This variable tells the name of the array holding the stdio streams. Usual values include _iob, __iob, and __sF.

strerror_r_proto

From d_strerror_r.U:

This variable encodes the prototype of strerror_r. It is zero if d_strerror_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_strerror_r is defined.

submit

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

subversion

From patchlevel.U:

The subversion level of this package. The value of subversion comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 1. In patchlevel.h, this is referred to as PERL_SUBVERSION. This is unique to perl.

sysman

From sysman.U:

This variable holds the place where the manual is located on this system. It is not the place where the user wants to put his manual pages. Rather it is the place where Configure may look to find manual for unix commands (section 1 of the manual usually). See mansrc.

sysroot

From Sysroot.U:

This variable is empty unless supplied by the Configure user. It can contain a path to an alternative root directory, under which headers and libraries for the compilation target can be found. This is generally used when cross-compiling using a gcc-like compiler.

t

tail

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

taint_disabled

From define: SILENT_NO_TAINT_SUPPORT or NO_TAINT_SUPPORT

If this perl is compiled with support for taint mode this variable will be set to the empty string, if it was compiled with SILENT_NO_TAINT_SUPPORT defined then it will be set to be "silent", and if it was compiled with NO_TAINT_SUPPORT defined it will be 'define'. Either of the above defines will results in it being a true value. This property was added in 5.37.11. See also "taint_support".

taint_support

From define: SILENT_NO_TAINT_SUPPORT or NO_TAINT_SUPPORT

If this perl is compiled with support for taint mode this variable will be set to 'define', if it is not it will be set to the empty string. Either of the above defines will result in it being empty. This property was added in version 5.37.11. See also "taint_disabled".

tar

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

targetarch

From Cross.U:

If cross-compiling, this variable contains the target architecture. If not, this will be empty.

targetdir

From Cross.U:

This variable contains a path that will be created on the target host using targetmkdir, and then used to copy the cross-compiled executables to. Defaults to /tmp if not set.

targetenv

From Cross.U:

If cross-compiling, this variable can be used to modify the environment on the target system. However, how and where it's used, and even if it's used at all, is entirely dependent on both the transport mechanism (targetrun) and what the target system is. Unless the relevant documentation says otherwise, it is genereally not useful.

targethost

From Cross.U:

This variable contains the name of a separate host machine that can be used to run compiled test programs and perl tests on. Set to empty string if not in use.

targetmkdir

From Cross.U:

This variable contains the command used by Configure to create a new directory on the target host.

targetport

From Cross.U:

This variable contains the number of a network port to be used to connect to the host in targethost, if unset defaults to 22 for ssh.

targetsh

From sh.U:

If cross-compiling, this variable contains the location of sh on the target system. If not, this will be the same as $sh.

tbl

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

tee

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

test

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the test program. After Configure runs, the value is reset to a plain test and is not useful.

timeincl

From i_time.U:

This variable holds the full path of the included time header(s).

timetype

From d_time.U:

This variable holds the type returned by time(). It can be long, or time_t on BSD sites (in which case <sys/types.h> should be included). Anyway, the type Time_t should be used.

tmpnam_r_proto

From d_tmpnam_r.U:

This variable encodes the prototype of tmpnam_r. It is zero if d_tmpnam_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_tmpnam_r is defined.

to

From Cross.U:

This variable contains the command used by Configure to copy to from the target host. Useful and available only during Perl build. The string : if not cross-compiling.

touch

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the touch program. After Configure runs, the value is reset to a plain touch and is not useful.

tr

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the tr program. After Configure runs, the value is reset to a plain tr and is not useful.

trnl

From trnl.U:

This variable contains the value to be passed to the tr(1) command to transliterate a newline. Typical values are \012 and \n. This is needed for EBCDIC systems where newline is not necessarily \012.

troff

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

ttyname_r_proto

From d_ttyname_r.U:

This variable encodes the prototype of ttyname_r. It is zero if d_ttyname_r is undef, and one of the REENTRANT_PROTO_T_ABC macros of reentr.h if d_ttyname_r is defined.

u

u16size

From perlxv.U:

This variable is the size of an U16 in bytes.

u16type

From perlxv.U:

This variable contains the C type used for Perl's U16.

u32XUformat

From perlx32f.U:

This variable contains the format string used for printing a Perl U32 as an unsigned hexadecimal integer in uppercase ABCDEF.

u32oformat

From perlx32f.U:

This variable contains the format string used for printing a Perl U32 as an unsigned octal integer.

u32size

From perlxv.U:

This variable is the size of an U32 in bytes.

u32type

From perlxv.U:

This variable contains the C type used for Perl's U32.

u32uformat

From perlx32f.U:

This variable contains the format string used for printing a Perl U32 as an unsigned decimal integer.

u32xformat

From perlx32f.U:

This variable contains the format string used for printing a Perl U32 as an unsigned hexadecimal integer in lowercase abcdef.

u64size

From perlxv.U:

This variable is the size of an U64 in bytes.

u64type

From perlxv.U:

This variable contains the C type used for Perl's U64.

u8size

From perlxv.U:

This variable is the size of an U8 in bytes.

u8type

From perlxv.U:

This variable contains the C type used for Perl's U8.

uidformat

From uidf.U:

This variable contains the format string used for printing a Uid_t.

uidsign

From uidsign.U:

This variable contains the signedness of a uidtype. 1 for unsigned, -1 for signed.

uidsize

From uidsize.U:

This variable contains the size of a uidtype in bytes.

uidtype

From uidtype.U:

This variable defines Uid_t to be something like uid_t, int, ushort, or whatever type is used to declare user ids in the kernel.

uname

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the uname program. After Configure runs, the value is reset to a plain uname and is not useful.

uniq

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the uniq program. After Configure runs, the value is reset to a plain uniq and is not useful.

uquadtype

From quadtype.U:

This variable defines Uquad_t to be something like unsigned long, unsigned int, unsigned long long, uint64_t, or whatever type is used for 64-bit integers.

use64bitall

From use64bits.U:

This variable conditionally defines the USE_64_BIT_ALL symbol, and indicates that 64-bit integer types should be used when available. The maximal possible 64-bitness is employed: LP64 or ILP64, meaning that you will be able to use more than 2 gigabytes of memory. This mode is even more binary incompatible than USE_64_BIT_INT. You may not be able to run the resulting executable in a 32-bit CPU at all or you may need at least to reboot your OS to 64-bit mode.

use64bitint

From use64bits.U:

This variable conditionally defines the USE_64_BIT_INT symbol, and indicates that 64-bit integer types should be used when available. The minimal possible 64-bitness is employed, just enough to get 64-bit integers into Perl. This may mean using for example "long longs", while your memory may still be limited to 2 gigabytes.

usecbacktrace

From usebacktrace.U:

This variable indicates whether we are compiling with backtrace support.

usecrosscompile

From Cross.U:

This variable conditionally defines the USE_CROSS_COMPILE symbol, and indicates that Perl has been cross-compiled.

usedefaultstrict

From usedefaultstrict.U:

This setting provides a mechanism for perl developers to enable strict by default. These defaults do not apply when perl is run via -e or -E.

usedevel

From Devel.U:

This variable indicates that Perl was configured with development features enabled. This should not be done for production builds.

usedl

From dlsrc.U:

This variable indicates if the system supports dynamic loading of some sort. See also dlsrc and dlobj.

usedtrace

From usedtrace.U:

This variable indicates whether we are compiling with dtrace support. See also dtrace.

usefaststdio

From usefaststdio.U:

This variable conditionally defines the USE_FAST_STDIO symbol, and indicates that Perl should be built to use fast stdio. Defaults to define in Perls 5.8 and earlier, to undef later.

useithreads

From usethreads.U:

This variable conditionally defines the USE_ITHREADS symbol, and indicates that Perl should be built to use the interpreter-based threading implementation.

usekernprocpathname

From usekernprocpathname.U:

This variable, indicates that we can use sysctl with KERN_PROC_PATHNAME to get a full path for the executable, and hence convert $^X to an absolute path.

uselanginfo

From Extensions.U:

This variable holds either true or false to indicate whether the I18N::Langinfo extension should be used. The sole use for this currently is to allow an easy mechanism for users to skip this extension from the Configure command line.

uselargefiles

From uselfs.U:

This variable conditionally defines the USE_LARGE_FILES symbol, and indicates that large file interfaces should be used when available.

uselongdouble

From uselongdbl.U:

This variable conditionally defines the USE_LONG_DOUBLE symbol, and indicates that long doubles should be used when available.

usemallocwrap

From mallocsrc.U:

This variable contains y if we are wrapping malloc to prevent integer overflow during size calculations.

usemorebits

From usemorebits.U:

This variable conditionally defines the USE_MORE_BITS symbol, and indicates that explicit 64-bit interfaces and long doubles should be used when available.

usemultiplicity

From usemultiplicity.U:

This variable conditionally defines the MULTIPLICITY symbol, and indicates that Perl should be built to use multiplicity.

usemymalloc

From mallocsrc.U:

This variable contains y if the malloc that comes with this package is desired over the system's version of malloc. People often include special versions of malloc for efficiency, but such versions are often less portable. See also mallocsrc and mallocobj. If this is y, then -lmalloc is removed from $libs.

usenm

From usenm.U:

This variable contains true or false depending whether the nm extraction is wanted or not.

usensgetexecutablepath

From usensgetexecutablepath.U:

This symbol, if defined, indicates that we can use _NSGetExecutablePath and realpath to get a full path for the executable, and hence convert $^X to an absolute path.

useopcode

From Extensions.U:

This variable holds either true or false to indicate whether the Opcode extension should be used. The sole use for this currently is to allow an easy mechanism for users to skip the Opcode extension from the Configure command line.

useperlio

From useperlio.U:

This variable conditionally defines the USE_PERLIO symbol, and indicates that the PerlIO abstraction should be used throughout.

useposix

From Extensions.U:

This variable holds either true or false to indicate whether the POSIX extension should be used. The sole use for this currently is to allow an easy mechanism for hints files to indicate that POSIX will not compile on a particular system.

usequadmath

From usequadmath.U:

This variable conditionally defines the USE_QUADMATH symbol, and indicates that the quadmath library __float128 long doubles should be used when available.

usereentrant

From usethreads.U:

This variable conditionally defines the USE_REENTRANT_API symbol, which indicates that the thread code may try to use the various _r versions of library functions. This is only potentially meaningful if usethreads is set and is very experimental, it is not even prompted for.

userelocatableinc

From bin.U:

This variable is set to true to indicate that perl should relocate @INC entries at runtime based on the path to the perl binary. Any @INC paths starting .../ are relocated relative to the directory containing the perl binary, and a logical cleanup of the path is then made around the join point (removing dir/../ pairs)

useshrplib

From libperl.U:

This variable is set to true if the user wishes to build a shared libperl, and false otherwise.

usesitecustomize

From d_sitecustomize.U:

This variable is set to true when the user requires a mechanism that allows the sysadmin to add entries to @INC at runtime. This variable being set, makes perl run $sitelib/sitecustomize.pl at startup.

usesocks

From usesocks.U:

This variable conditionally defines the USE_SOCKS symbol, and indicates that Perl should be built to use SOCKS.

usethreads

From usethreads.U:

This variable conditionally defines the USE_THREADS symbol, and indicates that Perl should be built to use threads.

usevendorprefix

From vendorprefix.U:

This variable tells whether the vendorprefix and consequently other vendor* paths are in use.

useversionedarchname

From archname.U:

This variable indicates whether to include the $api_versionstring as a component of the $archname.

usevfork

From d_vfork.U:

This variable is set to true when the user accepts to use vfork. It is set to false when no vfork is available or when the user explicitly requests not to use vfork.

usrinc

From usrinc.U:

This variable holds the path of the include files, which is usually /usr/include. It is mainly used by other Configure units.

uuname

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

uvXUformat

From perlxvf.U:

This variable contains the format string used for printing a Perl UV as an unsigned hexadecimal integer in uppercase ABCDEF.

uvoformat

From perlxvf.U:

This variable contains the format string used for printing a Perl UV as an unsigned octal integer.

uvsize

From perlxv.U:

This variable is the size of a UV in bytes.

uvtype

From perlxv.U:

This variable contains the C type used for Perl's UV.

uvuformat

From perlxvf.U:

This variable contains the format string used for printing a Perl UV as an unsigned decimal integer.

uvxformat

From perlxvf.U:

This variable contains the format string used for printing a Perl UV as an unsigned hexadecimal integer in lowercase abcdef.

v

vendorarch

From vendorarch.U:

This variable contains the value of the PERL_VENDORARCH symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own architecture-dependent modules and extensions in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorarchexp

From vendorarch.U:

This variable is the ~name expanded version of vendorarch, so that you may use it directly in Makefiles or shell scripts.

vendorbin

From vendorbin.U:

This variable contains the eventual value of the VENDORBIN symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place additional binaries in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorbinexp

From vendorbin.U:

This variable is the ~name expanded version of vendorbin, so that you may use it directly in Makefiles or shell scripts.

vendorhtml1dir

From vendorhtml1dir.U:

This variable contains the name of the directory for html pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own html pages in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorhtml1direxp

From vendorhtml1dir.U:

This variable is the ~name expanded version of vendorhtml1dir, so that you may use it directly in Makefiles or shell scripts.

vendorhtml3dir

From vendorhtml3dir.U:

This variable contains the name of the directory for html library pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own html pages for modules and extensions in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorhtml3direxp

From vendorhtml3dir.U:

This variable is the ~name expanded version of vendorhtml3dir, so that you may use it directly in Makefiles or shell scripts.

vendorlib

From vendorlib.U:

This variable contains the eventual value of the VENDORLIB symbol, which is the name of the private library for this package. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own modules in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorlib_stem

From vendorlib.U:

This variable is $vendorlibexp with any trailing version-specific component removed. The elements in inc_version_list (inc_version_list.U) can be tacked onto this variable to generate a list of directories to search.

vendorlibexp

From vendorlib.U:

This variable is the ~name expanded version of vendorlib, so that you may use it directly in Makefiles or shell scripts.

vendorman1dir

From vendorman1dir.U:

This variable contains the name of the directory for man1 pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own man1 pages in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorman1direxp

From vendorman1dir.U:

This variable is the ~name expanded version of vendorman1dir, so that you may use it directly in Makefiles or shell scripts.

vendorman3dir

From vendorman3dir.U:

This variable contains the name of the directory for man3 pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own man3 pages in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorman3direxp

From vendorman3dir.U:

This variable is the ~name expanded version of vendorman3dir, so that you may use it directly in Makefiles or shell scripts.

vendorprefix

From vendorprefix.U:

This variable holds the full absolute path of the directory below which the vendor will install add-on packages. See INSTALL for usage and examples.

vendorprefixexp

From vendorprefix.U:

This variable holds the full absolute path of the directory below which the vendor will install add-on packages. Derived from vendorprefix.

vendorscript

From vendorscript.U:

This variable contains the eventual value of the VENDORSCRIPT symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place additional executable scripts in this directory with MakeMaker Makefile.PL INSTALLDIRS=vendor or equivalent. See INSTALL for details.

vendorscriptexp

From vendorscript.U:

This variable is the ~name expanded version of vendorscript, so that you may use it directly in Makefiles or shell scripts.

version

From patchlevel.U:

The full version number of this package, such as 5.6.1 (or 5_6_1). This combines revision, patchlevel, and subversion to get the full version number, including any possible subversions. This is suitable for use as a directory name, and hence is filesystem dependent.

version_patchlevel_string

From patchlevel.U:

This is a string combining version, subversion and perl_patchlevel (if perl_patchlevel is non-zero). It is typically something like 'version 7 subversion 1' or 'version 7 subversion 1 patchlevel 11224' It is computed here to avoid duplication of code in myconfig.SH and lib/Config.pm.

versiononly

From versiononly.U:

If set, this symbol indicates that only the version-specific components of a perl installation should be installed. This may be useful for making a test installation of a new version without disturbing the existing installation. Setting versiononly is equivalent to setting installperl's -v option. In particular, the non-versioned scripts and programs such as a2p, c2ph, h2xs, pod2*, and perldoc are not installed (see INSTALL for a more complete list). Nor are the man pages installed. Usually, this is undef.

vi

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

x

xlibpth

From libpth.U:

This variable holds extra path (space-separated) used to find libraries on this platform, for example CPU-specific libraries (on multi-CPU platforms) may be listed here.

xlocale_needed

From d_newlocale.U:

This symbol, if defined, indicates that the C program should include <xlocale.h> to get newlocale() and its friends.

y

yacc

From yacc.U:

This variable holds the name of the compiler compiler we want to use in the Makefile. It can be yacc, byacc, or bison -y.

yaccflags

From yacc.U:

This variable contains any additional yacc flags desired by the user. It is up to the Makefile to use this.

z

zcat

From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

zip

From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the zip program. After Configure runs, the value is reset to a plain zip and is not useful.

GIT DATA

Information on the git commit from which the current perl binary was compiled can be found in the variable $Config::Git_Data. The variable is a structured string that looks something like this:

git_commit_id='ea0c2dbd5f5ac6845ecc7ec6696415bf8e27bd52'
git_describe='GitLive-blead-1076-gea0c2db'
git_branch='smartmatch'
git_uncommitted_changes=''
git_commit_id_title='Commit id:'
git_commit_date='2009-05-09 17:47:31 +0200'

Its format is not guaranteed not to change over time.

NOTE

This module contains a good example of how to use tie to implement a cache and an example of how to make a tied variable readonly to those outside of it.