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Perl 5.005 Documentation

For ease of access, the Perl manual has been split up into a number of sections:

perl                Perl overview (this section)
perldelta           Perl changes since previous version
perlfaq             Perl frequently asked questions
perltoc             Perl documentation table of contents

perldata            Perl data structures
perlsyn             Perl syntax
perlop              Perl operators and precedence
perlre              Perl regular expressions
perlrun             Perl execution and options
perlfunc            Perl builtin functions
perlvar             Perl predefined variables
perlsub             Perl subroutines
perlmod             Perl modules: how they work
perlmodlib          Perl modules: how to write and use
perlmodinstall      Perl modules: how to install from CPAN
perlform            Perl formats
perllocale          Perl locale support

perlref             Perl references
perldsc             Perl data structures intro
perllol             Perl data structures: lists of lists
perltoot            Perl OO tutorial
perlobj             Perl objects
perltie             Perl objects hidden behind simple variables
perlbot             Perl OO tricks and examples
perlipc             Perl interprocess communication

perldebug           Perl debugging
perldiag            Perl diagnostic messages
perlsec             Perl security
perltrap            Perl traps for the unwary
perlport            Perl portability guide
perlstyle           Perl style guide

perlpod             Perl plain old documentation
perlbook            Perl book information

perlembed           Perl ways to embed perl in your C or C++ application
perlapio            Perl internal IO abstraction interface
perlxs              Perl XS application programming interface
perlxstut           Perl XS tutorial
perlguts            Perl internal functions for those doing extensions
perlcall            Perl calling conventions from C

perlhist            Perl history records

(If you're intending to read these straight through for the first time, the suggested order will tend to reduce the number of forward references.)

By default, all of the above manpages are installed in the /usr/local/man/ directory.

Extensive additional documentation for Perl modules is available. The default configuration for perl will place this additional documentation in the /usr/local/lib/perl5/man directory (or else in the man subdirectory of the Perl library directory). Some of this additional documentation is distributed standard with Perl, but you'll also find documentation for third-party modules there.

You should be able to view Perl's documentation with your man(1) program by including the proper directories in the appropriate start-up files, or in the MANPATH environment variable. To find out where the configuration has installed the manpages, type:

perl -V:man.dir

If the directories have a common stem, such as /usr/local/man/man1 and /usr/local/man/man3, you need only to add that stem (/usr/local/man) to your man(1) configuration files or your MANPATH environment variable. If they do not share a stem, you'll have to add both stems.

If that doesn't work for some reason, you can still use the supplied perldoc script to view module information. You might also look into getting a replacement man program.

If something strange has gone wrong with your program and you're not sure where you should look for help, try the -w switch first. It will often point out exactly where the trouble is.

Full perl(1) documentation: perl

Reference Lists

About Perl

Perl is a language optimized for scanning arbitrary text files, extracting information from those text files, and printing reports based on that information. It's also a good language for many system management tasks. The language is intended to be practical (easy to use, efficient, complete) rather than beautiful (tiny, elegant, minimal).

Perl combines (in the author's opinion, anyway) some of the best features of C, sed, awk, and sh, so people familiar with those languages should have little difficulty with it. (Language historians will also note some vestiges of csh, Pascal, and even BASIC-PLUS.) Expression syntax corresponds quite closely to C expression syntax. Unlike most Unix utilities, Perl does not arbitrarily limit the size of your data--if you've got the memory, Perl can slurp in your whole file as a single string. Recursion is of unlimited depth. And the tables used by hashes (previously called "associative arrays") grow as necessary to prevent degraded performance. Perl uses sophisticated pattern matching techniques to scan large amounts of data very quickly. Although optimized for scanning text, Perl can also deal with binary data, and can make dbm files look like hashes. Setuid Perl scripts are safer than C programs through a dataflow tracing mechanism which prevents many stupid security holes.

If you have a problem that would ordinarily use sed or awk or sh, but it exceeds their capabilities or must run a little faster, and you don't want to write the silly thing in C, then Perl may be for you. There are also translators to turn your sed and awk scripts into Perl scripts.

But wait, there's more...

Perl version 5 is nearly a complete rewrite, and provides the following additional benefits:

Okay, that's definitely enough hype.