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CONTENTS

NAME

perlintern - autogenerated documentation of purely internal Perl functions

DESCRIPTION

This file is the autogenerated documentation of functions in the Perl interpreter that are documented using Perl's internal documentation format but are not marked as part of the Perl API. In other words, they are not for use in extensions!

It has the same sections as perlapi, though some may be empty.

AV Handling

av_fetch_simple

This is a cut-down version of av_fetch that assumes that the array is very straightforward - no magic, not readonly, and AvREAL - and that key is not negative. This function MUST NOT be used in situations where any of those assumptions may not hold.

Returns the SV at the specified index in the array. The key is the index. If lval is true, you are guaranteed to get a real SV back (in case it wasn't real before), which you can then modify. Check that the return value is non-null before dereferencing it to a SV*.

The rough perl equivalent is $myarray[$key].

    SV **       av_fetch_simple(      AV *av, SSize_t key, I32 lval)
    SV **  Perl_av_fetch_simple(pTHX_ AV *av, SSize_t key, I32 lval)
av_new_alloc

This implements "newAV_alloc_x" in perlapi and "newAV_alloc_xz" in perlapi, which are the public API for this functionality.

Creates a new AV and allocates its SV* array.

This is similar to, but more efficient than doing:

AV *av = newAV();
av_extend(av, key);

The size parameter is used to pre-allocate a SV* array large enough to hold at least elements 0..(size-1). size must be at least 1.

The zeroflag parameter controls whether or not the array is NULL initialized.

    AV *       av_new_alloc(      SSize_t size, bool zeroflag)
    AV *  Perl_av_new_alloc(pTHX_ SSize_t size, bool zeroflag)
av_store_simple

This is a cut-down version of av_store that assumes that the array is very straightforward - no magic, not readonly, and AvREAL - and that key is not negative. This function MUST NOT be used in situations where any of those assumptions may not hold.

Stores an SV in an array. The array index is specified as key. It can be dereferenced to get the SV* that was stored there (= val)).

Note that the caller is responsible for suitably incrementing the reference count of val before the call.

Approximate Perl equivalent: splice(@myarray, $key, 1, $val).

    SV **       av_store_simple(      AV *av, SSize_t key, SV *val)
    SV **  Perl_av_store_simple(pTHX_ AV *av, SSize_t key, SV *val)
AvFILLp

If the array av is empty, this returns -1; otherwise it returns the maximum value of the indices of all the array elements which are currently defined in av. It does not handle magic, hence the p private indication in its name.

    SSize_t  AvFILLp(AV* av)

Callback Functions

dowantarray

DEPRECATED! It is planned to remove dowantarray from a future release of Perl. Do not use it for new code; remove it from existing code.

Implements the deprecated "GIMME" in perlapi.

    U8       dowantarray()
    U8  Perl_dowantarray(pTHX)
leave_scope

Implements LEAVE_SCOPE which you should use instead.

    void       leave_scope(      I32 base)
    void  Perl_leave_scope(pTHX_ I32 base)
magic_freedestruct

This function is called via magic to implement the mortal_destructor_sv() and mortal_destructor_x() functions. It should not be called directly and has no user serviceable parts.

    int       magic_freedestruct(      SV *sv, MAGIC *mg)
    int  Perl_magic_freedestruct(pTHX_ SV *sv, MAGIC *mg)
mortal_svfunc_x

This function arranges for a C function reference to be called at the end of the current statement with the arguments provided. It is a wrapper around mortal_destructor_sv() which ensures that the latter function is called appropriately.

Be aware that there is a significant difference in timing between the end of the current statement and the end of the current pseudo block. If you are looking for a mechanism to trigger a function at the end of the current pseudo block you should look at "SAVEDESTRUCTOR_X" in perlapi instead of this function.

    void       mortal_svfunc_x(      SVFUNC_t f, SV *p)
    void  Perl_mortal_svfunc_x(pTHX_ SVFUNC_t f, SV *p)
pop_scope

Implements "LEAVE" in perlapi

    void       pop_scope()
    void  Perl_pop_scope(pTHX)
push_scope

Implements "ENTER" in perlapi

    void       push_scope()
    void  Perl_push_scope(pTHX)
save_adelete

Implements SAVEADELETE.

    void       save_adelete(      AV *av, SSize_t key)
    void  Perl_save_adelete(pTHX_ AV *av, SSize_t key)
save_freercpv

Implements SAVEFREERCPV.

Saves and frees a refcounted string. Calls rcpv_free() on the argument when the current pseudo block is finished.

    void       save_freercpv(      char *rcpv)
    void  Perl_save_freercpv(pTHX_ char *rcpv)
save_generic_pvref

Implements SAVEGENERICPV.

Like save_pptr(), but also Safefree()s the new value if it is different from the old one. Can be used to restore a global char* to its prior contents, freeing new value.

    void       save_generic_pvref(      char **str)
    void  Perl_save_generic_pvref(pTHX_ char **str)
save_generic_svref

Implements SAVEGENERICSV.

Like save_sptr(), but also SvREFCNT_dec()s the new value. Can be used to restore a global SV to its prior contents, freeing new value.

    void       save_generic_svref(      SV **sptr)
    void  Perl_save_generic_svref(pTHX_ SV **sptr)
save_hdelete

Implements SAVEHDELETE.

    void       save_hdelete(      HV *hv, SV *keysv)
    void  Perl_save_hdelete(pTHX_ HV *hv, SV *keysv)
save_hints

Implements SAVEHINTS.

    void       save_hints()
    void  Perl_save_hints(pTHX)
save_op

Implements SAVEOP.

    void       save_op()
    void  Perl_save_op(pTHX)
save_padsv_and_mortalize

Implements SAVEPADSVANDMORTALIZE.

    void       save_padsv_and_mortalize(      PADOFFSET off)
    void  Perl_save_padsv_and_mortalize(pTHX_ PADOFFSET off)
save_pushptr

The refcnt of object ptr will be decremented at the end of the current pseudo-block. type gives the type of ptr, expressed as one of the constants in scope.h whose name begins with SAVEt_.

This is the underlying implementation of several macros, like SAVEFREESV.

    void       save_pushptr(      void * const ptr, const int type)
    void  Perl_save_pushptr(pTHX_ void * const ptr, const int type)
save_rcpv

Implements SAVERCPV.

Saves and restores a refcounted string, similar to what save_generic_svref would do for a SV*. Can be used to restore a refcounted string to its previous state. Performs the appropriate refcount counting so that nothing should leak or be prematurely freed.

    void       save_rcpv(      char **prcpv)
    void  Perl_save_rcpv(pTHX_ char **prcpv)
save_scalar_at

A helper function for localizing the SV referenced by *sptr.

If SAVEf_KEEPOLDELEM is set in in flags, the function returns the input scalar untouched.

Otherwise it replaces *sptr with a new undef scalar, and returns that. The new scalar will have the old one's magic (if any) copied to it. If there is such magic, and SAVEf_SETMAGIC is set in in flags, 'set' magic will be processed on the new scalar. If unset, 'set' magic will be skipped. The latter typically means that assignment will soon follow (e.g., 'local $x = $y'), and that will handle the magic.

    SV *  save_scalar_at(SV **sptr, const U32 flags)
save_set_svflags

Implements SAVESETSVFLAGS.

Set the SvFLAGS specified by mask to the values in val

    void       save_set_svflags(      SV *sv, U32 mask, U32 val)
    void  Perl_save_set_svflags(pTHX_ SV *sv, U32 mask, U32 val)
save_shared_pvref

Implements SAVESHAREDPV.

Like save_generic_pvref(), but uses PerlMemShared_free() rather than Safefree(). Can be used to restore a shared global char* to its prior contents, freeing new value.

    void       save_shared_pvref(      char **str)
    void  Perl_save_shared_pvref(pTHX_ char **str)
save_vptr

Implements SAVEVPTR.

    void       save_vptr(      void *ptr)
    void  Perl_save_vptr(pTHX_ void *ptr)

Casting

There are currently no internal API items in Casting

Character case changing

There are currently no internal API items in Character case changing

Character classification

There are currently no internal API items in Character classification

Compiler and Preprocessor information

There are currently no internal API items in Compiler and Preprocessor information

Compiler directives

There are currently no internal API items in Compiler directives

Compile-time scope hooks

BhkENTRY

NOTE: BhkENTRY is experimental and may change or be removed without notice.

Return an entry from the BHK structure. which is a preprocessor token indicating which entry to return. If the appropriate flag is not set this will return NULL. The type of the return value depends on which entry you ask for.

    void *  BhkENTRY(BHK *hk, token which)
BhkFLAGS

NOTE: BhkFLAGS is experimental and may change or be removed without notice.

Return the BHK's flags.

    U32  BhkFLAGS(BHK *hk)
CALL_BLOCK_HOOKS

NOTE: CALL_BLOCK_HOOKS is experimental and may change or be removed without notice.

Call all the registered block hooks for type which. which is a preprocessing token; the type of arg depends on which.

    void  CALL_BLOCK_HOOKS(token which, arg)

Concurrency

CVf_SLABBED
CvROOT
CvSTART
CX_CUR
CX_LEAVE_SCOPE
CX_POP
cx_type
CXINC
cxstack
cxstack_ix
CXt_BLOCK
CXt_EVAL
CXt_FORMAT
CXt_LOOP_ARY
CXt_LOOP_LAZYIV
CXt_LOOP_LAZYSV
CXt_LOOP_LIST
CXt_LOOP_PLAIN
CXt_NULL
CXt_SUB
CXt_SUBST
dounwind

Described in perlguts.

    OP *                 CvROOT        (      CV * sv)
    OP *                 CvSTART       (      CV * sv)
                         CX_CUR        ()
    void                 CX_LEAVE_SCOPE(      PERL_CONTEXT* cx)
    void                 CX_POP        (      PERL_CONTEXT* cx)
    PERL_CONTEXT *       cxstack
    I32                  cxstack_ix
    void                 dounwind      (      I32 cxix)
    void            Perl_dounwind      (pTHX_ I32 cxix)
my_fork

This is for the use of PerlProc_fork as a wrapper for the C library fork(2) on some platforms to hide some platform quirks. It should not be used except through PerlProc_fork.

    Pid_t       my_fork()
    Pid_t  Perl_my_fork()
PERL_CONTEXT

Described in perlguts.

COPs and Hint Hashes

There are currently no internal API items in COPs and Hint Hashes

Custom Operators

core_prototype

This function assigns the prototype of the named core function to sv, or to a new mortal SV if sv is NULL. It returns the modified sv, or NULL if the core function has no prototype. code is a code as returned by keyword(). It must not be equal to 0.

    SV *       core_prototype(      SV *sv, const char *name,
                                    const int code,
                                    int * const opnum)
    SV *  Perl_core_prototype(pTHX_ SV *sv, const char *name,
                                    const int code,
                                    int * const opnum)

CV Handling

CvREFCOUNTED_ANYSV

If true, indicates that the CvXSUBANY(cv).any_sv member contains an SV pointer whose reference count should be decremented when the CV itself is freed. In addition, cv_clone() will increment the reference count, and sv_dup() will duplicate the entire pointed-to SV if this flag is set.

Any CV that wraps an XSUB has an ANY union that the XSUB function is free to use for its own purposes. It may be the case that the code wishes to store an SV in the any_sv member of this union. By setting this flag, this SV reference will be properly reclaimed or duplicated when the CV itself is.

    bool  CvREFCOUNTED_ANYSV(CV *cv)
CvREFCOUNTED_ANYSV_off

Helper macro to turn off the CvREFCOUNTED_ANYSV flag.

    void  CvREFCOUNTED_ANYSV_off(CV *cv)
CvREFCOUNTED_ANYSV_on

Helper macro to turn on the CvREFCOUNTED_ANYSV flag.

    void  CvREFCOUNTED_ANYSV_on(CV *cv)
CvWEAKOUTSIDE

Each CV has a pointer, CvOUTSIDE(), to its lexically enclosing CV (if any). Because pointers to anonymous sub prototypes are stored in & pad slots, it is a possible to get a circular reference, with the parent pointing to the child and vice-versa. To avoid the ensuing memory leak, we do not increment the reference count of the CV pointed to by CvOUTSIDE in the one specific instance that the parent has a & pad slot pointing back to us. In this case, we set the CvWEAKOUTSIDE flag in the child. This allows us to determine under what circumstances we should decrement the refcount of the parent when freeing the child.

There is a further complication with non-closure anonymous subs (i.e. those that do not refer to any lexicals outside that sub). In this case, the anonymous prototype is shared rather than being cloned. This has the consequence that the parent may be freed while there are still active children, e.g.,

BEGIN { $a = sub { eval '$x' } }

In this case, the BEGIN is freed immediately after execution since there are no active references to it: the anon sub prototype has CvWEAKOUTSIDE set since it's not a closure, and $a points to the same CV, so it doesn't contribute to BEGIN's refcount either. When $a is executed, the eval '$x' causes the chain of CvOUTSIDEs to be followed, and the freed BEGIN is accessed.

To avoid this, whenever a CV and its associated pad is freed, any & entries in the pad are explicitly removed from the pad, and if the refcount of the pointed-to anon sub is still positive, then that child's CvOUTSIDE is set to point to its grandparent. This will only occur in the single specific case of a non-closure anon prototype having one or more active references (such as $a above).

One other thing to consider is that a CV may be merely undefined rather than freed, eg undef &foo. In this case, its refcount may not have reached zero, but we still delete its pad and its CvROOT etc. Since various children may still have their CvOUTSIDE pointing at this undefined CV, we keep its own CvOUTSIDE for the time being, so that the chain of lexical scopes is unbroken. For example, the following should print 123:

my $x = 123;
sub tmp { sub { eval '$x' } }
my $a = tmp();
undef &tmp;
print  $a->();
    bool  CvWEAKOUTSIDE(CV *cv)
docatch

Interpose, for the current op and RUNOPS loop,

- a new JMPENV stack catch frame, and
- an inner RUNOPS loop to run all the remaining ops following the
  current PL_op.

Then handle any exceptions raised while in that loop. For a caught eval at this level, re-enter the loop with the specified restart op (i.e. the op following the OP_LEAVETRY etc); otherwise re-throw the exception.

docatch() is intended to be used like this:

PP(pp_entertry)
{
    if (CATCH_GET)
        return docatch(Perl_pp_entertry);

    ... rest of function ...
    return PL_op->op_next;
}

If a new catch frame isn't needed, the op behaves normally. Otherwise it calls docatch(), which recursively calls pp_entertry(), this time with CATCH_GET() false, so the rest of the body of the entertry is run. Then docatch() calls CALLRUNOPS() which executes all the ops following the entertry. When the loop finally finishes, control returns to docatch(), which pops the JMPENV and returns to the parent pp_entertry(), which itself immediately returns. Note that *all* subsequent ops are run within the inner RUNOPS loop, not just the body of the eval. For example, in

sub TIEARRAY { eval {1}; my $x }
tie @a, "main";

at the point the 'my' is executed, the C stack will look something like:

#10 main()
#9  perl_run()              # JMPENV_PUSH level 1 here
#8  S_run_body()
#7  Perl_runops_standard()  # main RUNOPS loop
#6  Perl_pp_tie()
#5  Perl_call_sv()
#4  Perl_runops_standard()  # unguarded RUNOPS loop: no new JMPENV
#3  Perl_pp_entertry()
#2  S_docatch()             # JMPENV_PUSH level 2 here
#1  Perl_runops_standard()  # docatch()'s RUNOPs loop
#0  Perl_pp_padsv()

Basically, any section of the perl core which starts a RUNOPS loop may make a promise that it will catch any exceptions and restart the loop if necessary. If it's not prepared to do that (like call_sv() isn't), then it sets CATCH_GET() to true, so that any later eval-like code knows to set up a new handler and loop (via docatch()).

See "Exception handing" in perlinterp for further details.

    OP *  docatch(Perl_ppaddr_t firstpp)

Debugging

comma_aDEPTH

Some functions when compiled under DEBUGGING take an extra final argument named depth, indicating the C stack depth. This argument is omitted otherwise. This macro expands to either , depth under DEBUGGING, or to nothing at all when not under DEBUGGING, reducing the number of #ifdef's in the code.

The program is responsible for maintaining the correct value for depth.

comma_pDEPTH

This is used in the prototype declarations for functions that take a "comma_aDEPTH" final parameter, much like pTHX_ is used in functions that take a thread context initial parameter.

debop

Implements -Dt perl command line option on OP o.

    I32       debop(      const OP *o)
    I32  Perl_debop(pTHX_ const OP *o)
debprof

Called to indicate that o was executed, for profiling purposes under the -DP command line option.

    void  debprof(const OP *o)
debprofdump

Dumps the contents of the data collected by the -DP perl command line option.

    void       debprofdump()
    void  Perl_debprofdump(pTHX)
debug_aDEPTH

Same as "comma_aDEPTH" but with no leading argument. Intended for functions with no normal arguments, and used by "comma_aDEPTH" itself.

debug_pDEPTH

Same as "comma_pDEPTH" but with no leading argument. Intended for functions with no normal arguments, and used by "comma_pDEPTH" itself.

free_c_backtrace

Deallocates a backtrace received from get_c_backtrace.

    void  free_c_backtrace(Perl_c_backtrace *bt)
get_c_backtrace

Collects the backtrace (aka "stacktrace") into a single linear malloced buffer, which the caller must Perl_free_c_backtrace().

Scans the frames back by depth + skip, then drops the skip innermost, returning at most depth frames.

    Perl_c_backtrace *       get_c_backtrace(      int max_depth,
                                                   int skip)
    Perl_c_backtrace *  Perl_get_c_backtrace(pTHX_ int max_depth,
                                                   int skip)
PL_DBsingle

When Perl is run in debugging mode, with the -d switch, this SV is a boolean which indicates whether subs are being single-stepped. Single-stepping is automatically turned on after every step. This is the C variable which corresponds to Perl's $DB::single variable. See "PL_DBsub".

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    SV *  PL_DBsingle
PL_DBsub

When Perl is run in debugging mode, with the -d switch, this GV contains the SV which holds the name of the sub being debugged. This is the C variable which corresponds to Perl's $DB::sub variable. See "PL_DBsingle".

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    GV *  PL_DBsub
PL_DBtrace

Trace variable used when Perl is run in debugging mode, with the -d switch. This is the C variable which corresponds to Perl's $DB::trace variable. See "PL_DBsingle".

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    SV *  PL_DBtrace
runops_debug
runops_standard

Described in perlguts.

    int       runops_debug   ()
    int  Perl_runops_debug   (pTHX)
    int       runops_standard()
    int  Perl_runops_standard(pTHX)

Display functions

sv_peek

Implements SvPEEK

    char *       sv_peek(      SV *sv)
    char *  Perl_sv_peek(pTHX_ SV *sv)

Embedding, Threads, and Interpreter Cloning

cv_dump

dump the contents of a CV

    void  cv_dump(const CV *cv, const char *title)
cv_forget_slab

When a CV has a reference count on its slab (CvSLABBED), it is responsible for making sure it is freed. (Hence, no two CVs should ever have a reference count on the same slab.) The CV only needs to reference the slab during compilation. Once it is compiled and CvROOT attached, it has finished its job, so it can forget the slab.

    void       cv_forget_slab(      CV *cv)
    void  Perl_cv_forget_slab(pTHX_ CV *cv)
do_dump_pad

Dump the contents of a padlist

    void       do_dump_pad(      I32 level, PerlIO *file,
                                 PADLIST *padlist, int full)
    void  Perl_do_dump_pad(pTHX_ I32 level, PerlIO *file,
                                 PADLIST *padlist, int full)
get_context

Implements "PERL_GET_CONTEXT" in perlapi, which you should use instead.

    void *       get_context()
    void *  Perl_get_context()
noshutdownhook

Stub that provides shutdown hook.

    void       noshutdownhook()
    void  Perl_noshutdownhook()
pad_alloc_name

Allocates a place in the currently-compiling pad (via "pad_alloc" in perlapi) and then stores a name for that entry. name is adopted and becomes the name entry; it must already contain the name string. typestash and ourstash and the padadd_STATE flag gets added to name. None of the other processing of "pad_add_name_pvn" in perlapi is done. Returns the offset of the allocated pad slot.

    PADOFFSET  pad_alloc_name(PADNAME *name, U32 flags,
                              NOCHECK HV *typestash, HV *ourstash)
pad_block_start

Update the pad compilation state variables on entry to a new block.

    void       pad_block_start(      int full)
    void  Perl_pad_block_start(pTHX_ int full)
pad_check_dup

Check for duplicate declarations: report any of:

* a 'my' in the current scope with the same name;
* an 'our' (anywhere in the pad) with the same name and the
  same stash as 'ourstash'

is_our indicates that the name to check is an "our" declaration.

    void  pad_check_dup(PADNAME *name, U32 flags, const HV *ourstash)
pad_findlex

Find a named lexical anywhere in a chain of nested pads. Add fake entries in the inner pads if it's found in an outer one.

Returns the offset in the bottom pad of the lex or the fake lex. cv is the CV in which to start the search, and seq is the current cop_seq to match against. If warn is true, print appropriate warnings. The out_* vars return values, and so are pointers to where the returned values should be stored. out_capture, if non-null, requests that the innermost instance of the lexical is captured; out_name is set to the innermost matched pad name or fake pad name; out_flags returns the flags normally associated with the PARENT_FAKELEX_FLAGS field of a fake pad name.

Note that pad_findlex() is recursive; it recurses up the chain of CVs, then comes back down, adding fake entries as it goes. It has to be this way because fake names in anon prototypes have to store in xpadn_low the index into the parent pad.

    PADOFFSET  pad_findlex(const char *namepv, STRLEN namelen,
                           U32 flags, const CV *cv, U32 seq,
                           int warn, SV **out_capture,
                           PADNAME **out_name, int *out_flags)
pad_fixup_inner_anons

For any anon CVs in the pad, change CvOUTSIDE of that CV from old_cv to new_cv if necessary. Needed when a newly-compiled CV has to be moved to a pre-existing CV struct.

    void       pad_fixup_inner_anons(      PADLIST *padlist,
                                           CV *old_cv, CV *new_cv)
    void  Perl_pad_fixup_inner_anons(pTHX_ PADLIST *padlist,
                                           CV *old_cv, CV *new_cv)
pad_free

Free the SV at offset po in the current pad.

    void       pad_free(      PADOFFSET po)
    void  Perl_pad_free(pTHX_ PADOFFSET po)
pad_leavemy

Cleanup at end of scope during compilation: set the max seq number for lexicals in this scope and warn of any lexicals that never got introduced.

    OP *       pad_leavemy()
    OP *  Perl_pad_leavemy(pTHX)
pad_push

Push a new pad frame onto the padlist, unless there's already a pad at this depth, in which case don't bother creating a new one. Then give the new pad an @_ in slot zero.

    void       pad_push(      PADLIST *padlist, int depth)
    void  Perl_pad_push(pTHX_ PADLIST *padlist, int depth)
pad_reset

Mark all the current temporaries for reuse

    void  pad_reset()
pad_setsv

Set the value at offset po in the current (compiling or executing) pad. Use the macro PAD_SETSV() rather than calling this function directly.

    void       pad_setsv(      PADOFFSET po, SV *sv)
    void  Perl_pad_setsv(pTHX_ PADOFFSET po, SV *sv)
pad_sv

Get the value at offset po in the current (compiling or executing) pad. Use macro PAD_SV instead of calling this function directly.

    SV *       pad_sv(      PADOFFSET po)
    SV *  Perl_pad_sv(pTHX_ PADOFFSET po)
pad_swipe

Abandon the tmp in the current pad at offset po and replace with a new one.

    void       pad_swipe(      PADOFFSET po, bool refadjust)
    void  Perl_pad_swipe(pTHX_ PADOFFSET po, bool refadjust)
padlist_dup

Duplicates a pad.

    PADLIST *       padlist_dup(      PADLIST *srcpad,
                                      CLONE_PARAMS *param)
    PADLIST *  Perl_padlist_dup(pTHX_ PADLIST *srcpad,
                                      CLONE_PARAMS *param)
padname_dup

Duplicates a pad name.

    PADNAME *       padname_dup(      PADNAME *src,
                                      CLONE_PARAMS *param)
    PADNAME *  Perl_padname_dup(pTHX_ PADNAME *src,
                                      CLONE_PARAMS *param)
padnamelist_dup

Duplicates a pad name list.

    PADNAMELIST *       padnamelist_dup(      PADNAMELIST *srcpad,
                                              CLONE_PARAMS *param)
    PADNAMELIST *  Perl_padnamelist_dup(pTHX_ PADNAMELIST *srcpad,
                                              CLONE_PARAMS *param)
set_context

Implements "PERL_SET_CONTEXT" in perlapi, which you should use instead.

    void       set_context(void *t)
    void  Perl_set_context(void *t)
si_dup

Duplicate a stack info structure, returning a pointer to the cloned object.

    PERL_SI *       si_dup(      PERL_SI *si, CLONE_PARAMS *param)
    PERL_SI *  Perl_si_dup(pTHX_ PERL_SI *si, CLONE_PARAMS *param)
ss_dup

Duplicate the save stack, returning a pointer to the cloned object.

    ANY *       ss_dup(      PerlInterpreter *proto_perl,
                             CLONE_PARAMS *param)
    ANY *  Perl_ss_dup(pTHX_ PerlInterpreter *proto_perl,
                             CLONE_PARAMS *param)

Errno

dSAVE_ERRNO

Declare variables needed to save errno and any operating system specific error number, and save them for optional later restoration by RESTORE_ERRNO.

    void  dSAVE_ERRNO
dSAVEDERRNO

Declare variables needed to save errno and any operating system specific error number.

    void  dSAVEDERRNO
RESTORE_ERRNO

Restore errno and any operating system specific error number that was saved by dSAVE_ERRNO or RESTORE_ERRNO.

    void  RESTORE_ERRNO
SAVE_ERRNO

Save errno and any operating system specific error number for optional later restoration by RESTORE_ERRNO. Requires dSAVEDERRNO or dSAVE_ERRNO in scope.

    void  SAVE_ERRNO
SETERRNO

Set errno, and on VMS set vaxc$errno.

    void  SETERRNO(int errcode, int vmserrcode)

Exception Handling (simple) Macros

There are currently no internal API items in Exception Handling (simple) Macros

Filesystem configuration values

There are currently no internal API items in Filesystem configuration values

Floating point

There are currently no internal API items in Floating point

General Configuration

There are currently no internal API items in General Configuration

Global Variables

There are currently no internal API items in Global Variables

GV Handling and Stashes

amagic_applies

Check sv to see if the overloaded (active magic) operation method applies to it. If the sv is not SvROK or it is not an object then returns false, otherwise checks if the object is blessed into a class supporting overloaded operations, and returns true if a call to amagic_call() with this SV and the given method would trigger an amagic operation, including via the overload fallback rules or via nomethod. Thus a call like:

amagic_applies(sv, string_amg, AMG_unary)

would return true for an object with overloading set up in any of the following ways:

use overload q("") => sub { ... };
use overload q(0+) => sub { ... }, fallback => 1;

and could be used to tell if a given object would stringify to something other than the normal default ref stringification.

Note that the fact that this function returns TRUE does not mean you can successfully perform the operation with amagic_call(), for instance any overloaded method might throw a fatal exception, however if this function returns FALSE you can be confident that it will NOT perform the given overload operation.

method is an integer enum, one of the values found in overload.h, for instance string_amg.

flags should be set to AMG_unary for unary operations.

    bool       amagic_applies(      SV *sv, int method, int flags)
    bool  Perl_amagic_applies(pTHX_ SV *sv, int method, int flags)
gp_dup

Duplicate a typeglob, returning a pointer to the cloned object.

    GP *       gp_dup(      GP * const gp,
                            CLONE_PARAMS * const param)
    GP *  Perl_gp_dup(pTHX_ GP * const gp,
                            CLONE_PARAMS * const param)
gv_handler

Implements StashHANDLER, which you should use instead

    CV *       gv_handler(      HV *stash, I32 id)
    CV *  Perl_gv_handler(pTHX_ HV *stash, I32 id)
gv_stashsvpvn_cached

Returns a pointer to the stash for a specified package, possibly cached. Implements both "gv_stashpvn" in perlapi and "gv_stashsv" in perlapi.

Requires one of either namesv or namepv to be non-null.

If the flag GV_CACHE_ONLY is set, return the stash only if found in the cache; see "gv_stashpvn" in perlapi for details on the other flags.

Note it is strongly preferred for namesv to be non-null, for performance reasons.

    HV *       gv_stashsvpvn_cached(      SV *namesv,
                                          const char *name,
                                          U32 namelen, I32 flags)
    HV *  Perl_gv_stashsvpvn_cached(pTHX_ SV *namesv,
                                          const char *name,
                                          U32 namelen, I32 flags)
gv_try_downgrade

NOTE: gv_try_downgrade is experimental and may change or be removed without notice.

If the typeglob gv can be expressed more succinctly, by having something other than a real GV in its place in the stash, replace it with the optimised form. Basic requirements for this are that gv is a real typeglob, is sufficiently ordinary, and is only referenced from its package. This function is meant to be used when a GV has been looked up in part to see what was there, causing upgrading, but based on what was found it turns out that the real GV isn't required after all.

If gv is a completely empty typeglob, it is deleted from the stash.

If gv is a typeglob containing only a sufficiently-ordinary constant sub, the typeglob is replaced with a scalar-reference placeholder that more compactly represents the same thing.

    void       gv_try_downgrade(      GV *gv)
    void  Perl_gv_try_downgrade(pTHX_ GV *gv)

Hook manipulation

There are currently no internal API items in Hook manipulation

HV Handling

hv_eiter_p

Implements HvEITER which you should use instead.

    HE **  Perl_hv_eiter_p(pTHX_ HV *hv)
hv_eiter_set

Implements HvEITER_set which you should use instead.

    void  Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter)
hv_ename_add

Adds a name to a stash's internal list of effective names. See "hv_ename_delete".

This is called when a stash is assigned to a new location in the symbol table.

    void       hv_ename_add(      HV *hv, const char *name, U32 len,
                                  U32 flags)
    void  Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len,
                                  U32 flags)
hv_ename_delete

Removes a name from a stash's internal list of effective names. If this is the name returned by HvENAME, then another name in the list will take its place (HvENAME will use it).

This is called when a stash is deleted from the symbol table.

    void       hv_ename_delete(      HV *hv, const char *name,
                                     U32 len, U32 flags)
    void  Perl_hv_ename_delete(pTHX_ HV *hv, const char *name,
                                     U32 len, U32 flags)
hv_fill

Returns the number of hash buckets that happen to be in use.

This function implements the HvFILL macro which you should use instead.

As of perl 5.25 this function is used only for debugging purposes, and the number of used hash buckets is not in any way cached, thus this function can be costly to execute as it must iterate over all the buckets in the hash.

    STRLEN  Perl_hv_fill(pTHX_ HV * const hv)
hv_placeholders_get

Implements HvPLACEHOLDERS_get, which you should use instead.

    I32  Perl_hv_placeholders_get(pTHX_ const HV *hv)
hv_placeholders_set

Implements HvPLACEHOLDERS_set, which you should use instead.

    void  Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
hv_riter_p

Implements HvRITER which you should use instead.

    I32 *  Perl_hv_riter_p(pTHX_ HV *hv)
hv_riter_set

Implements HvRITER_set which you should use instead.

    void  Perl_hv_riter_set(pTHX_ HV *hv, I32 riter)
refcounted_he_chain_2hv

Generates and returns a HV * representing the content of a refcounted_he chain. flags is currently unused and must be zero.

    HV *       refcounted_he_chain_2hv(const struct refcounted_he *c,
                                       U32 flags)
    HV *  Perl_refcounted_he_chain_2hv(pTHX_
                                       const struct refcounted_he *c,
                                       U32 flags)
refcounted_he_fetch_pv

Like "refcounted_he_fetch_pvn", but takes a nul-terminated string instead of a string/length pair.

    SV *       refcounted_he_fetch_pv(
                                  const struct refcounted_he *chain,
                                   const char *key, U32 hash,
                                   U32 flags)
    SV *  Perl_refcounted_he_fetch_pv(pTHX_
                                   const struct refcounted_he *chain,
                                   const char *key, U32 hash,
                                   U32 flags)
refcounted_he_fetch_pvn

Search along a refcounted_he chain for an entry with the key specified by keypv and keylen. If flags has the REFCOUNTED_HE_KEY_UTF8 bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1. hash is a precomputed hash of the key string, or zero if it has not been precomputed. Returns a mortal scalar representing the value associated with the key, or &PL_sv_placeholder if there is no value associated with the key.

    SV *       refcounted_he_fetch_pvn(
                                  const struct refcounted_he *chain,
                                   const char *keypv, STRLEN keylen,
                                   U32 hash, U32 flags)
    SV *  Perl_refcounted_he_fetch_pvn(pTHX_
                                   const struct refcounted_he *chain,
                                   const char *keypv, STRLEN keylen,
                                   U32 hash, U32 flags)
refcounted_he_fetch_pvs

Like "refcounted_he_fetch_pvn", but takes a literal string instead of a string/length pair, and no precomputed hash.

    SV *  refcounted_he_fetch_pvs(const struct refcounted_he *chain,
                                  "key", U32 flags)
refcounted_he_fetch_sv

Like "refcounted_he_fetch_pvn", but takes a Perl scalar instead of a string/length pair.

    SV *       refcounted_he_fetch_sv(
                                  const struct refcounted_he *chain,
                                   SV *key, U32 hash, U32 flags)
    SV *  Perl_refcounted_he_fetch_sv(pTHX_
                                   const struct refcounted_he *chain,
                                   SV *key, U32 hash, U32 flags)
refcounted_he_free

Decrements the reference count of a refcounted_he by one. If the reference count reaches zero the structure's memory is freed, which (recursively) causes a reduction of its parent refcounted_he's reference count. It is safe to pass a null pointer to this function: no action occurs in this case.

    void       refcounted_he_free(      struct refcounted_he *he)
    void  Perl_refcounted_he_free(pTHX_ struct refcounted_he *he)
refcounted_he_inc

Increment the reference count of a refcounted_he. The pointer to the refcounted_he is also returned. It is safe to pass a null pointer to this function: no action occurs and a null pointer is returned.

    struct refcounted_he *       refcounted_he_inc(
                                           struct refcounted_he *he)
    struct refcounted_he *  Perl_refcounted_he_inc(pTHX_
                                            struct refcounted_he *he)
refcounted_he_new_pv

Like "refcounted_he_new_pvn", but takes a nul-terminated string instead of a string/length pair.

    struct refcounted_he *       refcounted_he_new_pv(
                                       struct refcounted_he *parent,
                                        const char *key, U32 hash,
                                        SV *value, U32 flags)
    struct refcounted_he *  Perl_refcounted_he_new_pv(pTHX_
                                        struct refcounted_he *parent,
                                        const char *key, U32 hash,
                                        SV *value, U32 flags)
refcounted_he_new_pvn

Creates a new refcounted_he. This consists of a single key/value pair and a reference to an existing refcounted_he chain (which may be empty), and thus forms a longer chain. When using the longer chain, the new key/value pair takes precedence over any entry for the same key further along the chain.

The new key is specified by keypv and keylen. If flags has the REFCOUNTED_HE_KEY_UTF8 bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1. hash is a precomputed hash of the key string, or zero if it has not been precomputed.

value is the scalar value to store for this key. value is copied by this function, which thus does not take ownership of any reference to it, and later changes to the scalar will not be reflected in the value visible in the refcounted_he. Complex types of scalar will not be stored with referential integrity, but will be coerced to strings. value may be either null or &PL_sv_placeholder to indicate that no value is to be associated with the key; this, as with any non-null value, takes precedence over the existence of a value for the key further along the chain.

parent points to the rest of the refcounted_he chain to be attached to the new refcounted_he. This function takes ownership of one reference to parent, and returns one reference to the new refcounted_he.

    struct refcounted_he *       refcounted_he_new_pvn(
                                       struct refcounted_he *parent,
                                        const char *keypv,
                                        STRLEN keylen, U32 hash,
                                        SV *value, U32 flags)
    struct refcounted_he *  Perl_refcounted_he_new_pvn(pTHX_
                                        struct refcounted_he *parent,
                                        const char *keypv,
                                        STRLEN keylen, U32 hash,
                                        SV *value, U32 flags)
refcounted_he_new_pvs

Like "refcounted_he_new_pvn", but takes a literal string instead of a string/length pair, and no precomputed hash.

    struct refcounted_he *  refcounted_he_new_pvs(
                                       struct refcounted_he *parent,
                                        "key", SV *value, U32 flags)
refcounted_he_new_sv

Like "refcounted_he_new_pvn", but takes a Perl scalar instead of a string/length pair.

    struct refcounted_he *       refcounted_he_new_sv(
                                       struct refcounted_he *parent,
                                        SV *key, U32 hash, SV *value,
                                        U32 flags)
    struct refcounted_he *  Perl_refcounted_he_new_sv(pTHX_
                                        struct refcounted_he *parent,
                                        SV *key, U32 hash, SV *value,
                                        U32 flags)
unsharepvn

If no one has access to shared string str with length len, free it.

len and hash must both be valid for str.

    void       unsharepvn(      const char *sv, I32 len, U32 hash)
    void  Perl_unsharepvn(pTHX_ const char *sv, I32 len, U32 hash)

Input/Output

dirp_dup

Duplicate a directory handle, returning a pointer to the cloned object.

    DIR *       dirp_dup(      DIR * const dp,
                               CLONE_PARAMS * const param)
    DIR *  Perl_dirp_dup(pTHX_ DIR * const dp,
                               CLONE_PARAMS * const param)
fp_dup

Duplicate a file handle, returning a pointer to the cloned object.

    PerlIO *       fp_dup(      PerlIO * const fp, const char type,
                                CLONE_PARAMS * const param)
    PerlIO *  Perl_fp_dup(pTHX_ PerlIO * const fp, const char type,
                                CLONE_PARAMS * const param)
my_fflush_all

Implements PERL_FLUSHALL_FOR_CHILD on some platforms.

    I32       my_fflush_all()
    I32  Perl_my_fflush_all(pTHX)
my_mkostemp

The C library mkostemp(3) if available, or a Perl implementation of it.

    int  Perl_my_mkostemp(char *templte, int flags)
my_mkstemp

The C library mkstemp(3) if available, or a Perl implementation of it.

    int  Perl_my_mkstemp(char *templte)
PL_last_in_gv

The GV which was last used for a filehandle input operation. (<FH>)

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    GV*  PL_last_in_gv
PL_ofsgv

The glob containing the output field separator - *, in Perl space.

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    GV*  PL_ofsgv
PL_rs

The input record separator - $/ in Perl space.

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    SV*  PL_rs
start_glob

NOTE: start_glob is experimental and may change or be removed without notice.

Function called by do_readline to spawn a glob (or do the glob inside perl on VMS). This code used to be inline, but now perl uses File::Glob this glob starter is only used by miniperl during the build process, or when PERL_EXTERNAL_GLOB is defined. Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up.

    PerlIO *  Perl_start_glob(pTHX_ SV *tmpglob, IO *io)

Integer

There are currently no internal API items in Integer

I/O Formats

There are currently no internal API items in I/O Formats

Lexer interface

validate_proto

NOTE: validate_proto is experimental and may change or be removed without notice.

This function performs syntax checking on a prototype, proto. If warn is true, any illegal characters or mismatched brackets will trigger illegalproto warnings, declaring that they were detected in the prototype for name.

The return value is true if this is a valid prototype, and false if it is not, regardless of whether warn was true or false.

Note that NULL is a valid proto and will always return true.

    bool       validate_proto(      SV *name, SV *proto, bool warn,
                                    bool curstash)
    bool  Perl_validate_proto(pTHX_ SV *name, SV *proto, bool warn,
                                    bool curstash)

Locales

There are currently no internal API items in Locales

Magic

magic_clearhint

Triggered by a delete from %^H, records the key to PL_compiling.cop_hints_hash.

    int       magic_clearhint(      SV *sv, MAGIC *mg)
    int  Perl_magic_clearhint(pTHX_ SV *sv, MAGIC *mg)
magic_clearhints

Triggered by clearing %^H, resets PL_compiling.cop_hints_hash.

    int       magic_clearhints(      SV *sv, MAGIC *mg)
    int  Perl_magic_clearhints(pTHX_ SV *sv, MAGIC *mg)
magic_methcall

Invoke a magic method (like FETCH).

sv and mg are the tied thingy and the tie magic.

meth is the name of the method to call.

argc is the number of args (in addition to $self) to pass to the method.

The flags can be:

G_DISCARD     invoke method with G_DISCARD flag and don't
              return a value
G_UNDEF_FILL  fill the stack with argc pointers to
              PL_sv_undef

The arguments themselves are any values following the flags argument.

Returns the SV (if any) returned by the method, or NULL on failure.

    SV *  Perl_magic_methcall(pTHX_ SV *sv, const MAGIC *mg,
                                    SV *meth, U32 flags, U32 argc,
                                    ...)
magic_sethint

Triggered by a store to %^H, records the key/value pair to PL_compiling.cop_hints_hash. It is assumed that hints aren't storing anything that would need a deep copy. Maybe we should warn if we find a reference.

    int       magic_sethint(      SV *sv, MAGIC *mg)
    int  Perl_magic_sethint(pTHX_ SV *sv, MAGIC *mg)
mg_dup

Duplicate a chain of magic, returning a pointer to the cloned object.

    MAGIC *       mg_dup(      MAGIC *mg, CLONE_PARAMS * const param)
    MAGIC *  Perl_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS * const param)
mg_localize

Copy some of the magic from an existing SV to new localized version of that SV. Container magic (e.g., %ENV, $1, tie) gets copied, value magic doesn't (e.g., taint, pos).

If setmagic is false then no set magic will be called on the new (empty) SV. This typically means that assignment will soon follow (e.g. 'local $x = $y'), and that will handle the magic.

    void       mg_localize(      SV *sv, SV *nsv, bool setmagic)
    void  Perl_mg_localize(pTHX_ SV *sv, SV *nsv, bool setmagic)

Memory Management

calloc

Implements "Newxz" in perlapi which you should use instead.

    Malloc_t  Perl_calloc(MEM_SIZE elements, MEM_SIZE size)
malloc

Implements "Newx" in perlapi which you should use instead.

    Malloc_t  Perl_malloc(MEM_SIZE nbytes)
mfree

Implements "Safefree" in perlapi which you should use instead.

    Free_t  Perl_mfree(Malloc_t where)
realloc

Implements "Renew" in perlapi which you should use instead.

    Malloc_t  Perl_realloc(Malloc_t where, MEM_SIZE nbytes)

MRO

mro_get_linear_isa_dfs

Returns the Depth-First Search linearization of @ISA the given stash. The return value is a read-only AV* whose elements are string SVs giving class names. level should be 0 (it is used internally in this function's recursion).

You are responsible for SvREFCNT_inc() on the return value if you plan to store it anywhere semi-permanently (otherwise it might be deleted out from under you the next time the cache is invalidated).

    AV *  mro_get_linear_isa_dfs(HV *stash, U32 level)
mro_isa_changed_in

Takes the necessary steps (cache invalidations, mostly) when the @ISA of the given package has changed. Invoked by the setisa magic, should not need to invoke directly.

    void       mro_isa_changed_in(      HV *stash)
    void  Perl_mro_isa_changed_in(pTHX_ HV *stash)
mro_package_moved

Call this function to signal to a stash that it has been assigned to another spot in the stash hierarchy. stash is the stash that has been assigned. oldstash is the stash it replaces, if any. gv is the glob that is actually being assigned to.

This can also be called with a null first argument to indicate that oldstash has been deleted.

This function invalidates isa caches on the old stash, on all subpackages nested inside it, and on the subclasses of all those, including non-existent packages that have corresponding entries in stash.

It also sets the effective names (HvENAME) on all the stashes as appropriate.

If the gv is present and is not in the symbol table, then this function simply returns. This checked will be skipped if flags & 1.

    void       mro_package_moved(      HV * const stash,
                                       HV * const oldstash,
                                       const GV * const gv,
                                       U32 flags)
    void  Perl_mro_package_moved(pTHX_ HV * const stash,
                                       HV * const oldstash,
                                       const GV * const gv,
                                       U32 flags)

Multicall Functions

There are currently no internal API items in Multicall Functions

Numeric Functions

isinfnansv

Checks whether the argument would be either an infinity or NaN when used as a number, but is careful not to trigger non-numeric or uninitialized warnings. it assumes the caller has done SvGETMAGIC(sv) already.

Note that this always accepts trailing garbage (similar to grok_number_flags with PERL_SCAN_TRAILING), so "inferior" and "NAND gates" will return true.

    bool       isinfnansv(      SV *sv)
    bool  Perl_isinfnansv(pTHX_ SV *sv)

Optrees

newATTRSUB_x

Construct a Perl subroutine, also performing some surrounding jobs.

This function is expected to be called in a Perl compilation context, and some aspects of the subroutine are taken from global variables associated with compilation. In particular, PL_compcv represents the subroutine that is currently being compiled. It must be non-null when this function is called, and some aspects of the subroutine being constructed are taken from it. The constructed subroutine may actually be a reuse of the PL_compcv object, but will not necessarily be so.

If block is null then the subroutine will have no body, and for the time being it will be an error to call it. This represents a forward subroutine declaration such as sub foo ($$);. If block is non-null then it provides the Perl code of the subroutine body, which will be executed when the subroutine is called. This body includes any argument unwrapping code resulting from a subroutine signature or similar. The pad use of the code must correspond to the pad attached to PL_compcv. The code is not expected to include a leavesub or leavesublv op; this function will add such an op. block is consumed by this function and will become part of the constructed subroutine.

proto specifies the subroutine's prototype, unless one is supplied as an attribute (see below). If proto is null, then the subroutine will not have a prototype. If proto is non-null, it must point to a const op whose value is a string, and the subroutine will have that string as its prototype. If a prototype is supplied as an attribute, the attribute takes precedence over proto, but in that case proto should preferably be null. In any case, proto is consumed by this function.

attrs supplies attributes to be applied the subroutine. A handful of attributes take effect by built-in means, being applied to PL_compcv immediately when seen. Other attributes are collected up and attached to the subroutine by this route. attrs may be null to supply no attributes, or point to a const op for a single attribute, or point to a list op whose children apart from the pushmark are const ops for one or more attributes. Each const op must be a string, giving the attribute name optionally followed by parenthesised arguments, in the manner in which attributes appear in Perl source. The attributes will be applied to the sub by this function. attrs is consumed by this function.

If o_is_gv is false and o is null, then the subroutine will be anonymous. If o_is_gv is false and o is non-null, then o must point to a const OP, which will be consumed by this function, and its string value supplies a name for the subroutine. The name may be qualified or unqualified, and if it is unqualified then a default stash will be selected in some manner. If o_is_gv is true, then o doesn't point to an OP at all, but is instead a cast pointer to a GV by which the subroutine will be named.

If there is already a subroutine of the specified name, then the new sub will either replace the existing one in the glob or be merged with the existing one. A warning may be generated about redefinition.

If the subroutine has one of a few special names, such as BEGIN or END, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. In the case of BEGIN, the subroutine will be executed and the reference to it disposed of before this function returns.

The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. But a BEGIN subroutine, having already been executed, will quite likely have been destroyed already by the time this function returns, making it erroneous for the caller to make any use of the returned pointer. It is the caller's responsibility to ensure that it knows which of these situations applies.

    CV *       newATTRSUB_x(      I32 floor, OP *o, OP *proto,
                                  OP *attrs, OP *block, bool o_is_gv)
    CV *  Perl_newATTRSUB_x(pTHX_ I32 floor, OP *o, OP *proto,
                                  OP *attrs, OP *block, bool o_is_gv)
newMYSUB

Construct a Perl lexical subroutine, also performing some surrounding jobs, and returning a pointer to the constructed subroutine.

Similar in action to "newATTRSUB_x" in perlintern.

    CV *       newMYSUB(      I32 floor, OP *o, OP *proto, OP *attrs,
                              OP *block)
    CV *  Perl_newMYSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs,
                              OP *block)
newXS_len_flags

Construct an XS subroutine, also performing some surrounding jobs.

The subroutine will have the entry point subaddr. It will have the prototype specified by the nul-terminated string proto, or no prototype if proto is null. The prototype string is copied; the caller can mutate the supplied string afterwards. If filename is non-null, it must be a nul-terminated filename, and the subroutine will have its CvFILE set accordingly. By default CvFILE is set to point directly to the supplied string, which must be static. If flags has the XS_DYNAMIC_FILENAME bit set, then a copy of the string will be taken instead.

Other aspects of the subroutine will be left in their default state. If anything else needs to be done to the subroutine for it to function correctly, it is the caller's responsibility to do that after this function has constructed it. However, beware of the subroutine potentially being destroyed before this function returns, as described below.

If name is null then the subroutine will be anonymous, with its CvGV referring to an __ANON__ glob. If name is non-null then the subroutine will be named accordingly, referenced by the appropriate glob. name is a string of length len bytes giving a sigilless symbol name, in UTF-8 if flags has the SVf_UTF8 bit set and in Latin-1 otherwise. The name may be either qualified or unqualified, with the stash defaulting in the same manner as for gv_fetchpvn_flags. flags may contain flag bits understood by gv_fetchpvn_flags with the same meaning as they have there, such as GV_ADDWARN. The symbol is always added to the stash if necessary, with GV_ADDMULTI semantics.

If there is already a subroutine of the specified name, then the new sub will replace the existing one in the glob. A warning may be generated about the redefinition. If the old subroutine was CvCONST then the decision about whether to warn is influenced by an expectation about whether the new subroutine will become a constant of similar value. That expectation is determined by const_svp. (Note that the call to this function doesn't make the new subroutine CvCONST in any case; that is left to the caller.) If const_svp is null then it indicates that the new subroutine will not become a constant. If const_svp is non-null then it indicates that the new subroutine will become a constant, and it points to an SV* that provides the constant value that the subroutine will have.

If the subroutine has one of a few special names, such as BEGIN or END, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. In the case of BEGIN, the subroutine will be executed and the reference to it disposed of before this function returns, and also before its prototype is set. If a BEGIN subroutine would not be sufficiently constructed by this function to be ready for execution then the caller must prevent this happening by giving the subroutine a different name.

The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. But a BEGIN subroutine, having already been executed, will quite likely have been destroyed already by the time this function returns, making it erroneous for the caller to make any use of the returned pointer. It is the caller's responsibility to ensure that it knows which of these situations applies.

    CV *       newXS_len_flags(      const char *name, STRLEN len,
                                     XSUBADDR_t subaddr,
                                     const char * const filename,
                                     const char * const proto,
                                     SV ** const_svp, U32 flags)
    CV *  Perl_newXS_len_flags(pTHX_ const char *name, STRLEN len,
                                     XSUBADDR_t subaddr,
                                     const char * const filename,
                                     const char * const proto,
                                     SV ** const_svp, U32 flags)
op_refcnt_lock

Implements the OP_REFCNT_LOCK macro which you should use instead.

    void       op_refcnt_lock()
    void  Perl_op_refcnt_lock(pTHX)
op_refcnt_unlock

Implements the OP_REFCNT_UNLOCK macro which you should use instead.

    void       op_refcnt_unlock()
    void  Perl_op_refcnt_unlock(pTHX)
traverse_op_tree

Return the next op in a depth-first traversal of the op tree, returning NULL when the traversal is complete.

The initial call must supply the root of the tree as both top and o.

For now it's static, but it may be exposed to the API in the future.

    OP *  traverse_op_tree(OP *top, OP *o)

Pack and Unpack

There are currently no internal API items in Pack and Unpack

Pad Data Structures

CX_CURPAD_SAVE

Save the current pad in the given context block structure.

    void  CX_CURPAD_SAVE(struct context)
CX_CURPAD_SV

Access the SV at offset po in the saved current pad in the given context block structure (can be used as an lvalue).

    SV *  CX_CURPAD_SV(struct context, PADOFFSET po)
PAD_BASE_SV

Get the value from slot po in the base (DEPTH=1) pad of a padlist

    SV *  PAD_BASE_SV(PADLIST padlist, PADOFFSET po)
PAD_CLONE_VARS

Clone the state variables associated with running and compiling pads.

    void  PAD_CLONE_VARS(PerlInterpreter *proto_perl,
                         CLONE_PARAMS* param)
PAD_COMPNAME_FLAGS

Return the flags for the current compiling pad name at offset po. Assumes a valid slot entry.

    U32  PAD_COMPNAME_FLAGS(PADOFFSET po)
PAD_COMPNAME_GEN

The generation number of the name at offset po in the current compiling pad (lvalue).

    STRLEN  PAD_COMPNAME_GEN(PADOFFSET po)
PAD_COMPNAME_GEN_set

Sets the generation number of the name at offset po in the current ling pad (lvalue) to gen.

    STRLEN  PAD_COMPNAME_GEN_set(PADOFFSET po, int gen)
PAD_COMPNAME_OURSTASH

Return the stash associated with an our variable. Assumes the slot entry is a valid our lexical.

    HV *  PAD_COMPNAME_OURSTASH(PADOFFSET po)
PAD_COMPNAME_PV

Return the name of the current compiling pad name at offset po. Assumes a valid slot entry.

    char *  PAD_COMPNAME_PV(PADOFFSET po)
PAD_COMPNAME_TYPE

Return the type (stash) of the current compiling pad name at offset po. Must be a valid name. Returns null if not typed.

    HV *  PAD_COMPNAME_TYPE(PADOFFSET po)
PAD_RESTORE_LOCAL

Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL()

    void  PAD_RESTORE_LOCAL(PAD *opad)
PAD_SAVE_LOCAL

Save the current pad to the local variable opad, then make the current pad equal to npad

    void  PAD_SAVE_LOCAL(PAD *opad, PAD *npad)
PAD_SAVE_SETNULLPAD

Save the current pad then set it to null.

    void  PAD_SAVE_SETNULLPAD()
PAD_SET_CUR

Set the current pad to be pad n in the padlist, saving the previous current pad. NB currently this macro expands to a string too long for some compilers, so it's best to replace it with

SAVECOMPPAD();
PAD_SET_CUR_NOSAVE(padlist,n);
    void  PAD_SET_CUR(PADLIST padlist, I32 n)
PAD_SET_CUR_NOSAVE

like PAD_SET_CUR, but without the save

    void  PAD_SET_CUR_NOSAVE(PADLIST padlist, I32 n)
PAD_SETSV

Set the slot at offset po in the current pad to sv

    SV *  PAD_SETSV(PADOFFSET po, SV* sv)
PAD_SV

Get the value at offset po in the current pad

    SV *  PAD_SV(PADOFFSET po)
PAD_SVl

Lightweight and lvalue version of PAD_SV. Get or set the value at offset po in the current pad. Unlike PAD_SV, does not print diagnostics with -DX. For internal use only.

    SV *  PAD_SVl(PADOFFSET po)
PadnameIsFIELD

Whether this is a "field" variable. PADNAMEs where this is true will have additional information available via PadnameFIELDINFO.

    bool  PadnameIsFIELD(PADNAME * pn)
PadnameIsOUR

Whether this is an "our" variable.

    bool  PadnameIsOUR(PADNAME * pn)
PadnameIsSTATE

Whether this is a "state" variable.

    bool  PadnameIsSTATE(PADNAME * pn)
PadnameOURSTASH

The stash in which this "our" variable was declared.

    HV *  PadnameOURSTASH(PADNAME * pn)
PadnameOUTER

Whether this entry belongs to an outer pad. Entries for which this is true are often referred to as 'fake'.

    bool  PadnameOUTER(PADNAME * pn)
PadnameTYPE

The stash associated with a typed lexical. This returns the %Foo:: hash for my Foo $bar.

    HV *  PadnameTYPE(PADNAME * pn)
SAVECLEARSV

Clear the pointed to pad value on scope exit. (i.e. the runtime action of my)

    void  SAVECLEARSV(SV **svp)
SAVECOMPPAD

save PL_comppad and PL_curpad

    void  SAVECOMPPAD()
SAVEPADSV

Save a pad slot (used to restore after an iteration)

    void  SAVEPADSV(PADOFFSET po)

Password and Group access

There are currently no internal API items in Password and Group access

Paths to system commands

There are currently no internal API items in Paths to system commands

Prototype information

There are currently no internal API items in Prototype information

Reference-counted stack manipulation

There are currently no internal API items in Reference-counted stack manipulation

REGEXP Functions

regnode

Described in perlreguts.

Reports and Formats

There are currently no internal API items in Reports and Formats

Signals

There are currently no internal API items in Signals

Site configuration

There are currently no internal API items in Site configuration

Sockets configuration values

There are currently no internal API items in Sockets configuration values

Source Filters

There are currently no internal API items in Source Filters

Stack Manipulation Macros

djSP

Declare Just SP. This is actually identical to dSP, and declares a local copy of perl's stack pointer, available via the SP macro. See "SP" in perlapi. (Available for backward source code compatibility with the old (Perl 5.005) thread model.)

    djSP();
LVRET

True if this op will be the return value of an lvalue subroutine

save_alloc

Implements "SSNEW" in perlapi and kin, which should be used instead of this function.

    SSize_t       save_alloc(      SSize_t size, I32 pad)
    SSize_t  Perl_save_alloc(pTHX_ SSize_t size, I32 pad)

String Handling

delimcpy_no_escape

Copy a source buffer to a destination buffer, stopping at (but not including) the first occurrence in the source of the delimiter byte, delim. The source is the bytes between from and from_end - 1. Similarly, the dest is to up to to_end.

The number of bytes copied is written to *retlen.

Returns the position of delim in the from buffer, but if there is no such occurrence before from_end, then from_end is returned, and the entire buffer from .. from_end - 1 is copied.

If there is room in the destination available after the copy, an extra terminating safety NUL byte is appended (not included in the returned length).

The error case is if the destination buffer is not large enough to accommodate everything that should be copied. In this situation, a value larger than to_end - to is written to *retlen, and as much of the source as fits will be written to the destination. Not having room for the safety NUL is not considered an error.

    char *       delimcpy_no_escape(char *to, const char *to_end,
                                    const char *from,
                                    const char *from_end,
                                    const int delim, I32 *retlen)
    char *  Perl_delimcpy_no_escape(char *to, const char *to_end,
                                    const char *from,
                                    const char *from_end,
                                    const int delim, I32 *retlen)
my_cxt_init

Implements the "MY_CXT_INIT" in perlxs macro, which you should use instead.

The first time a module is loaded, the global PL_my_cxt_index is incremented, and that value is assigned to that module's static my_cxt_index (whose address is passed as an arg). Then, for each interpreter this function is called for, it makes sure a void* slot is available to hang the static data off, by allocating or extending the interpreter's PL_my_cxt_list array

    void *  Perl_my_cxt_init(pTHX_ int *indexp, size_t size)
quadmath_format_needed

quadmath_format_needed() returns true if the format string seems to contain at least one non-Q-prefixed %[efgaEFGA] format specifier, or returns false otherwise.

The format specifier detection is not complete printf-syntax detection, but it should catch most common cases.

If true is returned, those arguments should in theory be processed with quadmath_snprintf(), but in case there is more than one such format specifier (see "quadmath_format_valid"), and if there is anything else beyond that one (even just a single byte), they cannot be processed because quadmath_snprintf() is very strict, accepting only one format spec, and nothing else. In this case, the code should probably fail.

    bool       quadmath_format_needed(const char *format)
    bool  Perl_quadmath_format_needed(const char *format)
quadmath_format_valid

quadmath_snprintf() is very strict about its format string and will fail, returning -1, if the format is invalid. It accepts exactly one format spec.

quadmath_format_valid() checks that the intended single spec looks sane: begins with %, has only one %, ends with [efgaEFGA], and has Q before it. This is not a full "printf syntax check", just the basics.

Returns true if it is valid, false if not.

See also "quadmath_format_needed".

    bool       quadmath_format_valid(const char *format)
    bool  Perl_quadmath_format_valid(const char *format)

SV Flags

SVt_INVLIST

Type flag for scalars. See "svtype" in perlapi.

SV Handling

PL_Sv

A scratch pad SV for whatever temporary use you need. Chiefly used as a fallback by macros on platforms where "PERL_USE_GCC_BRACE_GROUPS" in perlapi> is unavailable, and which would otherwise evaluate their SV parameter more than once.

BUT BEWARE, if this is used in a situation where something that is using it is in a call stack with something else that is using it, this variable would get zapped, leading to hard-to-diagnose errors.

sv_add_arena

Given a chunk of memory, link it to the head of the list of arenas, and split it into a list of free SVs.

    void  sv_add_arena(char * const ptr, const U32 size,
                       const U32 flags)
sv_clean_all

Decrement the refcnt of each remaining SV, possibly triggering a cleanup. This function may have to be called multiple times to free SVs which are in complex self-referential hierarchies.

    SSize_t       sv_clean_all()
    SSize_t  Perl_sv_clean_all(pTHX)
sv_clean_objs

Attempt to destroy all objects not yet freed.

    void       sv_clean_objs()
    void  Perl_sv_clean_objs(pTHX)
sv_free_arenas

Deallocate the memory used by all arenas. Note that all the individual SV heads and bodies within the arenas must already have been freed.

    void       sv_free_arenas()
    void  Perl_sv_free_arenas(pTHX)
sv_grow

Expands the character buffer in the SV. If necessary, uses sv_unref and upgrades the SV to SVt_PV. Returns a pointer to the character buffer. Use the SvGROW wrapper instead.

    char *       sv_grow(      SV * const sv, STRLEN newlen)
    char *  Perl_sv_grow(pTHX_ SV * const sv, STRLEN newlen)
sv_grow_fresh

A cut-down version of sv_grow intended only for when sv is a freshly-minted SVt_PV, SVt_PVIV, SVt_PVNV, or SVt_PVMG. i.e. sv has the default flags, has never been any other type, and does not have an existing string. Basically, just assigns a char buffer and returns a pointer to it.

    char *       sv_grow_fresh(      SV * const sv, STRLEN newlen)
    char *  Perl_sv_grow_fresh(pTHX_ SV * const sv, STRLEN newlen)
sv_newref

Increment an SV's reference count. Use the SvREFCNT_inc() wrapper instead.

    SV *       sv_newref(      SV * const sv)
    SV *  Perl_sv_newref(pTHX_ SV * const sv)
sv_pv

Use the SvPV_nolen macro instead

    char *       sv_pv(      SV *sv)
    char *  Perl_sv_pv(pTHX_ SV *sv)
sv_pvbyte

Use SvPVbyte_nolen instead.

    char *       sv_pvbyte(      SV *sv)
    char *  Perl_sv_pvbyte(pTHX_ SV *sv)
sv_pvbyten_force

The backend for the SvPVbytex_force macro. Always use the macro instead. If the SV cannot be downgraded from UTF-8, this croaks.

    char *       sv_pvbyten_force(      SV * const sv,
                                        STRLEN * const lp)
    char *  Perl_sv_pvbyten_force(pTHX_ SV * const sv,
                                        STRLEN * const lp)
sv_pvn_force

Get a sensible string out of the SV somehow. A private implementation of the SvPV_force macro for compilers which can't cope with complex macro expressions. Always use the macro instead.

    char *       sv_pvn_force(      SV *sv, STRLEN *lp)
    char *  Perl_sv_pvn_force(pTHX_ SV *sv, STRLEN *lp)
sv_pvutf8

Use the SvPVutf8_nolen macro instead

    char *       sv_pvutf8(      SV *sv)
    char *  Perl_sv_pvutf8(pTHX_ SV *sv)
sv_pvutf8n_force

The backend for the SvPVutf8x_force macro. Always use the macro instead.

    char *       sv_pvutf8n_force(      SV * const sv,
                                        STRLEN * const lp)
    char *  Perl_sv_pvutf8n_force(pTHX_ SV * const sv,
                                        STRLEN * const lp)
sv_tainted

Test an SV for taintedness. Use SvTAINTED instead.

    bool       sv_tainted(      SV * const sv)
    bool  Perl_sv_tainted(pTHX_ SV * const sv)
sv_true

Returns true if the SV has a true value by Perl's rules. Use the SvTRUE macro instead, which may call sv_true() or may instead use an in-line version.

    I32       sv_true(      SV * const sv)
    I32  Perl_sv_true(pTHX_ SV * const sv)
sv_untaint

Untaint an SV. Use SvTAINTED_off instead.

    void       sv_untaint(      SV * const sv)
    void  Perl_sv_untaint(pTHX_ SV * const sv)
sv_2bool

This macro is only used by sv_true() or its macro equivalent, and only if the latter's argument is neither SvPOK, SvIOK nor SvNOK. It calls sv_2bool_flags with the SV_GMAGIC flag.

    bool       sv_2bool(      SV * const sv)
    bool  Perl_sv_2bool(pTHX_ SV * const sv)
sv_2bool_flags

This function is only used by sv_true() and friends, and only if the latter's argument is neither SvPOK, SvIOK nor SvNOK. If the flags contain SV_GMAGIC, then it does an mg_get() first.

    bool       sv_2bool_flags(      SV *sv, I32 flags)
    bool  Perl_sv_2bool_flags(pTHX_ SV *sv, I32 flags)
sv_2num

NOTE: sv_2num is experimental and may change or be removed without notice.

Return an SV with the numeric value of the source SV, doing any necessary reference or overload conversion. The caller is expected to have handled get-magic already.

    SV *       sv_2num(      SV * const sv)
    SV *  Perl_sv_2num(pTHX_ SV * const sv)
sv_2pv_nolen

Like sv_2pv(), but doesn't return the length too. You should usually use the macro wrapper SvPV_nolen(sv) instead.

    char *       sv_2pv_nolen(      SV *sv)
    char *  Perl_sv_2pv_nolen(pTHX_ SV *sv)
sv_2pvbyte_nolen

Return a pointer to the byte-encoded representation of the SV. May cause the SV to be downgraded from UTF-8 as a side-effect.

Usually accessed via the SvPVbyte_nolen macro.

    char *       sv_2pvbyte_nolen(      SV *sv)
    char *  Perl_sv_2pvbyte_nolen(pTHX_ SV *sv)
sv_2pvutf8_nolen

Return a pointer to the UTF-8-encoded representation of the SV. May cause the SV to be upgraded to UTF-8 as a side-effect.

Usually accessed via the SvPVutf8_nolen macro.

    char *       sv_2pvutf8_nolen(      SV *sv)
    char *  Perl_sv_2pvutf8_nolen(pTHX_ SV *sv)
SvTHINKFIRST

A quick flag check to see whether an sv should be passed to sv_force_normal to be "downgraded" before SvIVX or SvPVX can be modified directly.

For example, if your scalar is a reference and you want to modify the SvIVX slot, you can't just do SvROK_off, as that will leak the referent.

This is used internally by various sv-modifying functions, such as sv_setsv, sv_setiv and sv_pvn_force.

One case that this does not handle is a gv without SvFAKE set. After

if (SvTHINKFIRST(gv)) sv_force_normal(gv);

it will still be a gv.

SvTHINKFIRST sometimes produces false positives. In those cases sv_force_normal does nothing.

    U32  SvTHINKFIRST(SV *sv)

Tainting

sv_taint

Taint an SV. Use SvTAINTED_on instead.

    void       sv_taint(      SV *sv)
    void  Perl_sv_taint(pTHX_ SV *sv)
TAINT

If we aren't in taint checking mode, do nothing; otherwise indicate to "TAINT_set" and "TAINT_PROPER" that some unspecified element is tainted.

    void  TAINT
TAINT_ENV

Looks at several components of %ENV for taintedness, and calls "taint_proper" if any are tainted. The components it searches are things like $PATH.

    void  TAINT_ENV()
taint_env

Implements the "TAINT_ENV" macro, which you should generally use instead.

    void       taint_env()
    void  Perl_taint_env(pTHX)
TAINT_get

Returns a boolean as to whether some element is tainted or not.

    bool  TAINT_get
TAINT_IF

If c evaluates to true, call "TAINT" to indicate that something is tainted; otherwise do nothing.

    void  TAINT_IF(bool c)
TAINT_NOT

Remove any taintedness previously set by, e.g., TAINT.

    void  TAINT_NOT
TAINT_PROPER

If no element is tainted, do nothing; otherwise output a message (containing s) that indicates there is a tainting violation. If such violations are fatal, it croaks.

    void  TAINT_PROPER(const char * s)
taint_proper

Implements the "TAINT_PROPER" macro, which you should generally use instead.

    void       taint_proper(      const char *f,
                                  const char * const s)
    void  Perl_taint_proper(pTHX_ const char *f,
                                  const char * const s)
TAINT_set

If s is true, "TAINT_get" returns true; If s is false, "TAINT_get" returns false;

    void  TAINT_set(bool s)
TAINT_WARN_get

Returns false if tainting violations are fatal; Returns true if they're just warnings

    bool  TAINT_WARN_get
TAINT_WARN_set

s being true indicates "TAINT_WARN_get" should return that tainting violations are just warnings

s being false indicates "TAINT_WARN_get" should return that tainting violations are fatal.

    void  TAINT_WARN_set(bool s)
TAINTING_get

Returns a boolean as to whether taint checking is enabled or not.

    bool  TAINTING_get
TAINTING_set

Turn taint checking mode off/on

    void  TAINTING_set(bool s)

Time

There are currently no internal API items in Time

Typedef names

There are currently no internal API items in Typedef names

Unicode Support

is_utf8_non_invariant_string

Returns TRUE if "is_utf8_invariant_string" in perlapi returns FALSE for the first len bytes of the string s, but they are, nonetheless, legal Perl-extended UTF-8; otherwise returns FALSE.

A TRUE return means that at least one code point represented by the sequence either is a wide character not representable as a single byte, or the representation differs depending on whether the sequence is encoded in UTF-8 or not.

See also "is_utf8_invariant_string" in perlapi.

    bool       is_utf8_non_invariant_string(const U8 * const s,
                                            STRLEN len)
    bool  Perl_is_utf8_non_invariant_string(const U8 * const s,
                                            STRLEN len)
isSCRIPT_RUN

Returns a bool as to whether or not the sequence of bytes from s up to but not including send form a "script run". utf8_target is TRUE iff the sequence starting at s is to be treated as UTF-8. To be precise, except for two degenerate cases given below, this function returns TRUE iff all code points in it come from any combination of three "scripts" given by the Unicode "Script Extensions" property: Common, Inherited, and possibly one other. Additionally all decimal digits must come from the same consecutive sequence of 10.

For example, if all the characters in the sequence are Greek, or Common, or Inherited, this function will return TRUE, provided any decimal digits in it are from the same block of digits in Common. (These are the ASCII digits "0".."9" and additionally a block for full width forms of these, and several others used in mathematical notation.) For scripts (unlike Greek) that have their own digits defined this will accept either digits from that set or from one of the Common digit sets, but not a combination of the two. Some scripts, such as Arabic, have more than one set of digits. All digits must come from the same set for this function to return TRUE.

*ret_script, if ret_script is not NULL, will on return of TRUE contain the script found, using the SCX_enum typedef. Its value will be SCX_INVALID if the function returns FALSE.

If the sequence is empty, TRUE is returned, but *ret_script (if asked for) will be SCX_INVALID.

If the sequence contains a single code point which is unassigned to a character in the version of Unicode being used, the function will return TRUE, and the script will be SCX_Unknown. Any other combination of unassigned code points in the input sequence will result in the function treating the input as not being a script run.

The returned script will be SCX_Inherited iff all the code points in it are from the Inherited script.

Otherwise, the returned script will be SCX_Common iff all the code points in it are from the Inherited or Common scripts.

    bool       isSCRIPT_RUN(      const U8 *s, const U8 *send,
                                  const bool utf8_target)
    bool  Perl_isSCRIPT_RUN(pTHX_ const U8 *s, const U8 *send,
                                  const bool utf8_target)
utf8_to_uvuni

DEPRECATED! It is planned to remove utf8_to_uvuni from a future release of Perl. Do not use it for new code; remove it from existing code.

Returns the Unicode code point of the first character in the string s which is assumed to be in UTF-8 encoding; retlen will be set to the length, in bytes, of that character.

Some, but not all, UTF-8 malformations are detected, and in fact, some malformed input could cause reading beyond the end of the input buffer, which is one reason why this function is deprecated. The other is that only in extremely limited circumstances should the Unicode versus native code point be of any interest to you.

If s points to one of the detected malformations, and UTF8 warnings are enabled, zero is returned and *retlen is set (if retlen doesn't point to NULL) to -1. If those warnings are off, the computed value if well-defined (or the Unicode REPLACEMENT CHARACTER, if not) is silently returned, and *retlen is set (if retlen isn't NULL) so that (s + *retlen) is the next possible position in s that could begin a non-malformed character. See "utf8n_to_uvchr" in perlapi for details on when the REPLACEMENT CHARACTER is returned.

    UV       utf8_to_uvuni(      const U8 *s, STRLEN *retlen)
    UV  Perl_utf8_to_uvuni(pTHX_ const U8 *s, STRLEN *retlen)
utf8n_to_uvuni

DEPRECATED! It is planned to remove utf8n_to_uvuni from a future release of Perl. Do not use it for new code; remove it from existing code.

Instead use "utf8_to_uvchr_buf" in perlapi, or rarely, "utf8n_to_uvchr" in perlapi.

This function was useful for code that wanted to handle both EBCDIC and ASCII platforms with Unicode properties, but starting in Perl v5.20, the distinctions between the platforms have mostly been made invisible to most code, so this function is quite unlikely to be what you want. If you do need this precise functionality, use instead NATIVE_TO_UNI(utf8_to_uvchr_buf(...)) or NATIVE_TO_UNI(utf8n_to_uvchr(...)).

    UV       utf8n_to_uvuni(      const U8 *s, STRLEN curlen,
                                  STRLEN *retlen, U32 flags)
    UV  Perl_utf8n_to_uvuni(pTHX_ const U8 *s, STRLEN curlen,
                                  STRLEN *retlen, U32 flags)
uvoffuni_to_utf8_flags

THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Instead, Almost all code should use "uv_to_utf8" in perlapi or "uv_to_utf8_flags" in perlapi.

This function is like them, but the input is a strict Unicode (as opposed to native) code point. Only in very rare circumstances should code not be using the native code point.

For details, see the description for "uv_to_utf8_flags" in perlapi.

    U8 *       uvoffuni_to_utf8_flags(      U8 *d, UV uv, UV flags)
    U8 *  Perl_uvoffuni_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags)
valid_utf8_to_uvchr

Like "utf8_to_uvchr_buf" in perlapi, but should only be called when it is known that the next character in the input UTF-8 string s is well-formed (e.g., it passes "isUTF8_CHAR" in perlapi. Surrogates, non-character code points, and non-Unicode code points are allowed.

    UV       valid_utf8_to_uvchr(const U8 *s, STRLEN *retlen)
    UV  Perl_valid_utf8_to_uvchr(const U8 *s, STRLEN *retlen)
variant_under_utf8_count

This function looks at the sequence of bytes between s and e, which are assumed to be encoded in ASCII/Latin1, and returns how many of them would change should the string be translated into UTF-8. Due to the nature of UTF-8, each of these would occupy two bytes instead of the single one in the input string. Thus, this function returns the precise number of bytes the string would expand by when translated to UTF-8.

Unlike most of the other functions that have utf8 in their name, the input to this function is NOT a UTF-8-encoded string. The function name is slightly odd to emphasize this.

This function is internal to Perl because khw thinks that any XS code that would want this is probably operating too close to the internals. Presenting a valid use case could change that.

See also "is_utf8_invariant_string" in perlapi and "is_utf8_invariant_string_loc" in perlapi,

    Size_t  variant_under_utf8_count(const U8 * const s,
                                     const U8 * const e)

Utility Functions

my_popen_list

Implementing function on some systems for PerlProc_popen_list()

    PerlIO *       my_popen_list(      const char *mode, int n,
                                       SV **args)
    PerlIO *  Perl_my_popen_list(pTHX_ const char *mode, int n,
                                       SV **args)
my_socketpair

Emulates socketpair(2) on systems that don't have it, but which do have enough functionality for the emulation.

    int       my_socketpair(int family, int type, int protocol,
                            int fd[2])
    int  Perl_my_socketpair(int family, int type, int protocol,
                            int fd[2])

Versioning

There are currently no internal API items in Versioning

Warning and Dieing

deprecate

Wrapper around Perl_ck_warner_d() to produce a deprecated warning in the given category with an appropriate message. The message argument must be a C string. The string " is deprecated" will automatically be added to the end of the message.

    deprecate(U32 category, "message")
deprecate_disappears_in

Wrapper around Perl_ck_warner_d() to produce a deprecated warning in the given category with an appropriate message that the construct referred to by the message will disappear in a specific release. The when and message arguments must be a C string. The when string is expected to be of the form "5.40", with no minor element in the version. The actual message output will be the result of the following expression message " is deprecated, and will disappear in Perl " when which is why message and when must be literal C strings.

    deprecate_disappears_in(U32 category, "when", "message")
deprecate_fatal_in

Wrapper around Perl_ck_warner_d() to produce a deprecated warning in the given category with an appropriate message that the construct referred to by the message will become fatal in a specific release. The when and message arguments must be a C string. The when string is expected to be of the form "5.40", with no minor element in the version. The actual message output will be the result of the following expression message " is deprecated, and will become fatal in Perl " when which is why message and when must be literal C strings.

    deprecate_fatal_in(U32 category, "when", "message")
find_uninit_var

NOTE: find_uninit_var is experimental and may change or be removed without notice.

Find the name of the undefined variable (if any) that caused the operator to issue a "Use of uninitialized value" warning. If match is true, only return a name if its value matches uninit_sv. So roughly speaking, if a unary operator (such as OP_COS) generates a warning, then following the direct child of the op may yield an OP_PADSV or OP_GV that gives the name of the undefined variable. On the other hand, with OP_ADD there are two branches to follow, so we only print the variable name if we get an exact match. desc_p points to a string pointer holding the description of the op. This may be updated if needed.

The name is returned as a mortal SV.

Assumes that PL_op is the OP that originally triggered the error, and that PL_comppad/PL_curpad points to the currently executing pad.

    SV *  find_uninit_var(const OP * const obase,
                          const SV * const uninit_sv, bool match,
                          const char **desc_p)
PL_dowarn

The C variable that roughly corresponds to Perl's $^W warning variable. However, $^W is treated as a boolean, whereas PL_dowarn is a collection of flag bits.

On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.

    U8  PL_dowarn
report_uninit

Print appropriate "Use of uninitialized variable" warning.

    void       report_uninit(      const SV *uninit_sv)
    void  Perl_report_uninit(pTHX_ const SV *uninit_sv)

XS

There are currently no internal API items in XS

Undocumented elements

This section lists the elements that are otherwise undocumented. If you use any of them, please consider creating and submitting documentation for it.

Experimental and deprecated undocumented elements are listed separately at the end.

abort_execution
add_above_Latin1_folds
add_cp_to_invlist
_add_range_to_invlist
allocmy
amagic_cmp
amagic_cmp_desc
amagic_cmp_locale
amagic_cmp_locale_desc
amagic_i_ncmp
amagic_i_ncmp_desc
amagic_is_enabled
amagic_ncmp
amagic_ncmp_desc
any_dup
append_utf8_from_native_byte
apply
atfork_lock
atfork_unlock
av_arylen_p
av_extend_guts
av_iter_p
av_nonelem
av_reify
bind_match
block_gimme
boot_core_builtin
boot_core_mro
boot_core_PerlIO
boot_core_UNIVERSAL
build_infix_plugin
_byte_dump_string
call_list
cando
capture_clear
cast_iv
cast_i32
cast_ulong
cast_uv
check_hash_fields_and_hekify
check_regnode_after
check_utf8_print
ck_anoncode
ck_backtick
ck_bitop
ck_classname
ck_cmp
ck_concat
ck_defined
ck_delete
ck_each
ck_entersub_args_core
ck_eof
ck_eval
ck_exec
ck_exists
ck_ftst
ck_fun
ck_glob
ck_grep
ck_helemexistsor
ck_index
ck_isa
ck_join
ck_length
ck_lfun
ck_listiob
ck_match
ck_method
ck_null
ck_open
ck_prototype
ck_readline
ck_refassign
ck_repeat
ck_require
ck_return
ck_rfun
ck_rvconst
ck_sassign
ck_scmp
ck_select
ck_shift
ck_sort
ck_spair
ck_split
ck_stringify
ck_subr
ck_substr
ck_svconst
ck_tell
ck_trunc
ck_trycatch
ckwarn
ckwarn_d
class_add_ADJUST
class_add_field
class_apply_attributes
class_apply_field_attributes
class_prepare_initfield_parse
class_prepare_method_parse
class_seal_stash
class_set_field_defop
class_setup_stash
class_wrap_method_body
clear_defarray
closest_cop
cmp_desc
cmp_locale_desc
cmpchain_extend
cmpchain_finish
cmpchain_start
cntrl_to_mnemonic
construct_ahocorasick_from_trie
cop_file_avn
coresub_op
croak_caller
croak_kw_unless_class
croak_memory_wrap
croak_no_mem
croak_no_mem_ext
croak_popstack
csighandler
csighandler1
csighandler3
current_re_engine
custom_op_get_field
cv_clone_into
cv_const_sv_or_av
cv_undef_flags
cvgv_from_hek
cvgv_set
cvstash_set
cx_dump
cx_dup
cxinc
deb_stack_all
debstackptrs
debug_hash_seed
debug_peep
debug_show_study_flags
debug_studydata
defelem_target
despatch_signals
die_unwind
do_aexec
do_aexec5
do_aspawn
do_eof
do_exec
do_exec3
do_gv_dump
do_gvgv_dump
do_hv_dump
do_ipcctl
do_ipcget
do_magic_dump
do_msgrcv
do_msgsnd
do_ncmp
do_op_dump
do_pmop_dump
do_print
do_readline
do_seek
do_semop
do_shmio
do_spawn
do_spawn_nowait
do_sv_dump
do_sysseek
do_tell
do_trans
do_uniprop_match
do_vecget
do_vecset
do_vop
does_utf8_overflow
dofile
doing_taint
doref
drand48_init_r
drand48_r
dtrace_probe_call
dtrace_probe_load
dtrace_probe_op
dtrace_probe_phase
dump_all_perl
dump_indent
dump_packsubs_perl
dump_sub_perl
dump_sv_child
dump_vindent
dumpuntil
dup_warnings
find_first_differing_byte_pos
find_lexical_cv
find_runcv_where
find_script
finish_export_lexical
foldEQ_latin1
foldEQ_latin1_s2_folded
foldEQ_utf8_flags
force_locale_unlock
force_out_malformed_utf8_message_
form_alien_digit_msg
form_cp_too_large_msg
free_tied_hv_pool
free_tmps
get_and_check_backslash_N_name
get_ANYOFHbbm_contents
get_ANYOFM_contents
get_db_sub
get_debug_opts
get_deprecated_property_msg
get_extended_os_errno
get_hash_seed
get_invlist_iter_addr
get_invlist_offset_addr
get_invlist_previous_index_addr
get_mstats
get_prop_definition
get_prop_values
get_re_gclass_aux_data
get_regclass_aux_data
get_regex_charset_name
get_win32_message_utf8ness
getenv_len
gp_free
gp_ref
grok_bin_oct_hex
grok_bslash_c
grok_bslash_o
grok_bslash_x
gv_check
gv_fetchmeth_internal
gv_override
gv_setref
gv_stashpvn_internal
he_dup
hek_dup
hfree_next_entry
hv_auxalloc
hv_common
hv_common_key_len
hv_delayfree_ent
hv_free_ent
hv_placeholders_p
hv_pushkv
hv_rand_set
hv_undef_flags
import_builtin_bundle
infix_plugin_standard
init_argv_symbols
init_constants
init_dbargs
init_debugger
init_i18nl10n
init_named_cv
init_stacks
init_tm
init_uniprops
_inverse_folds
invert
invlist_array
_invlist_array_init
invlist_clear
invlist_clone
_invlist_contains_cp
invlist_contents
_invlist_dump
invlist_extend
invlist_highest
_invlist_intersection_maybe_complement_2nd
_invlist_intersection
_invlist_invert
invlist_is_iterating
invlist_iterfinish
invlist_iterinit
invlist_iternext
_invlist_len
invlist_max
invlist_previous_index
_invlist_search
invlist_set_len
invlist_set_previous_index
_invlist_subtract
invlist_trim
_invlist_union_maybe_complement_2nd
_invlist_union
_invlistEQ
invmap_dump
invoke_exception_hook
io_close
is_grapheme
is_in_locale_category_
is_invlist
is_standard_filehandle_name
_is_uni_FOO
_is_uni_perl_idcont
_is_uni_perl_idstart
is_utf8_char_helper_
is_utf8_common
is_utf8_FF_helper_
_is_utf8_FOO
is_utf8_overlong
_is_utf8_perl_idcont
_is_utf8_perl_idstart
isFF_overlong
jmaybe
join_exact
keyword
keyword_plugin_standard
list
load_charnames
locale_panic
localize
lossless_NV_to_IV
lsbit_pos32
lsbit_pos64
magic_clear_all_env
magic_cleararylen_p
magic_clearenv
magic_clearhook
magic_clearhookall
magic_clearisa
magic_clearpack
magic_clearsig
magic_copycallchecker
magic_existspack
magic_freearylen_p
magic_freecollxfrm
magic_freemglob
magic_freeovrld
magic_freeutf8
magic_get
magic_getarylen
magic_getdebugvar
magic_getdefelem
magic_getnkeys
magic_getpack
magic_getpos
magic_getsig
magic_getsubstr
magic_gettaint
magic_getuvar
magic_getvec
magic_killbackrefs
magic_nextpack
magic_regdata_cnt
magic_regdatum_get
magic_regdatum_set
magic_scalarpack
magic_set
magic_set_all_env
magic_setarylen
magic_setcollxfrm
magic_setdbline
magic_setdebugvar
magic_setdefelem
magic_setenv
magic_sethook
magic_sethookall
magic_setisa
magic_setlvref
magic_setmglob
magic_setnkeys
magic_setnonelem
magic_setpack
magic_setpos
magic_setregexp
magic_setsig
magic_setsigall
magic_setsubstr
magic_settaint
magic_setutf8
magic_setuvar
magic_setvec
magic_sizepack
magic_wipepack
make_trie
malloc_good_size
malloced_size
markstack_grow
mbtowc_
mem_collxfrm_
mem_log_alloc
mem_log_del_sv
mem_log_free
mem_log_new_sv
mem_log_realloc
mg_find_mglob
mg_size
mode_from_discipline
more_bodies
more_sv
moreswitches
mortal_getenv
mortalized_pv_copy
mro_get_private_data
mro_meta_dup
mro_meta_init
msbit_pos32
msbit_pos64
multiconcat_stringify
multideref_stringify
my_atof2
my_atof3
my_attrs
my_clearenv
my_lstat
my_lstat_flags
my_memrchr
my_mkostemp_cloexec
my_mkstemp_cloexec
my_stat
my_stat_flags
my_strerror
my_unexec
_new_invlist_C_array
_new_invlist
new_stackinfo
new_stackinfo_flags
new_sv
newFORM
newMETHOP_internal
newPROG
newSTUB
newSVavdefelem
newXS_deffile
nextargv
no_bareword_allowed
no_bareword_filehandle
noperl_die
notify_parser_that_encoding_changed
oopsAV
oopsHV
op_clear
op_integerize
op_lvalue_flags
op_prune_chain_head
op_relocate_sv
op_std_init
op_varname
opmethod_stash
opslab_force_free
opslab_free
opslab_free_nopad
opslab_slot_offset
package
package_version
pad_add_weakref
padlist_store
padname_free
PadnameIN_SCOPE
padnamelist_free
parse_unicode_opts
parser_dup
parser_free
parser_free_nexttoke_ops
path_is_searchable
peep
perl_alloc_using
perl_clone_using
PerlEnv_putenv
PerlIO_context_layers
PerlIO_restore_errno
PerlIO_save_errno
PerlLIO_dup_cloexec
PerlLIO_dup2_cloexec
PerlLIO_open_cloexec
PerlLIO_open3_cloexec
PerlProc_pipe_cloexec
PerlSock_accept_cloexec
PerlSock_socket_cloexec
PerlSock_socketpair_cloexec
perly_sighandler
pmruntime
POPMARK
populate_anyof_bitmap_from_invlist
populate_bitmap_from_invlist
populate_invlist_from_bitmap
populate_isa
pregfree
pregfree2
prepare_export_lexical
ptr_hash
qerror
re_exec_indentf
re_indentf
re_intuit_start
re_intuit_string
re_op_compile
re_printf
ReANY
reentrant_free
reentrant_init
reentrant_retry
reentrant_size
ref
reg_add_data
reg_named_buff
reg_named_buff_all
reg_named_buff_exists
reg_named_buff_fetch
reg_named_buff_firstkey
reg_named_buff_iter
reg_named_buff_nextkey
reg_named_buff_scalar
reg_numbered_buff_fetch
reg_numbered_buff_fetch_flags
reg_numbered_buff_length
reg_numbered_buff_store
reg_qr_package
reg_skipcomment
reg_temp_copy
regcurly
regdump
regdupe_internal
regexec_flags
regfree_internal
reginitcolors
regnext
regnode_after
regprop
report_evil_fh
report_redefined_cv
report_wrongway_fh
resume_compcv
rpeep
rsignal_restore
rsignal_save
rvpv_dup
rxres_save
same_dirent
save_bool
save_clearsv
save_delete
save_destructor
save_destructor_x
save_freeop
save_freepv
save_freesv
save_int
save_iv
save_I8
save_I16
save_I32
save_mortalizesv
save_pptr
save_pushi32ptr
save_pushptrptr
save_re_context
save_sptr
save_strlen
savestack_grow
savestack_grow_cnt
sawparens
scalar
scalarvoid
scan_commit
scan_num
seed
set_ANYOF_arg
set_caret_X
set_numeric_standard
set_numeric_underlying
set_padlist
setfd_cloexec
setfd_cloexec_for_nonsysfd
setfd_cloexec_or_inhexec_by_sysfdness
setfd_inhexec
setfd_inhexec_for_sysfd
_setup_canned_invlist
share_hek
should_warn_nl
should_we_output_Debug_r
sighandler
sighandler1
sighandler3
single_1bit_pos32
single_1bit_pos64
size_to_psize
Slab_Alloc
Slab_Free
Slab_to_ro
Slab_to_rw
softref2xv
sortsv_flags_impl
ssc_init
stack_grow
str_to_version
strxfrm
study_chunk
sub_crush_depth
sv_add_backref
sv_buf_to_ro
sv_del_backref
sv_i_ncmp
sv_i_ncmp_desc
sv_magicext_mglob
sv_mark_arenas
sv_ncmp
sv_ncmp_desc
sv_only_taint_gmagic
sv_or_pv_pos_u2b
sv_pvbyten_force_wrapper
sv_pvutf8n_force_wrapper
sv_resetpvn
sv_sethek
sv_sweep_arenas
sv_unglob
sv_2iv
sv_2nv
sv_2uv
SvTRUE_common
switch_locale_context
sys_init
sys_init3
sys_intern_clear
sys_intern_dup
sys_intern_init
sys_term
tied_method
tmps_grow_p
_to_fold_latin1
to_uni_fold
_to_uni_fold_flags
to_uni_lower
to_uni_title
to_uni_upper
_to_upper_title_latin1
_to_utf8_fold_flags
_to_utf8_lower_flags
_to_utf8_title_flags
_to_utf8_upper_flags
TOPMARK
translate_substr_offsets
try_amagic_bin
try_amagic_un
uiv_2buf
unlnk
unshare_hek
unwind_paren
utf8_to_bytes_
utf8_to_uv_msgs_helper_
utf16_to_utf8
utf16_to_utf8_base
utf16_to_utf8_reversed
utilize
uvoffuni_to_utf8_flags_msgs
variant_byte_number
varname
vivify_defelem
vivify_ref
wait4pid
warn_elem_scalar_context
warn_problematic_locale
was_lvalue_sub
watch
win32_croak_not_implemented
write_to_stderr
xs_boot_epilog
XS_builtin_indexed
xs_handshake
yyerror
yyerror_pv
yyerror_pvn
yylex
yyparse
yyquit
yyunlex

Next are the experimental undocumented elements

alloc_LOGOP            hv_backreferences_p
av_remove_offset       hv_kill_backrefs
clear_defarray_simple  invlist_highest_range_start
create_eval_scope      invlist_lowest
cv_ckproto_len_flags   new_warnings_bitfield
cx_popblock            newGP
cx_popeval             op_refcnt_dec
cx_popformat           op_refcnt_inc
cx_poploop             op_unscope
cx_popsub              pop_stackinfo
cx_popsub_args         pp_wrap
cx_popsub_common       push_stackinfo
cx_pushblock           rpp_free_2_
cx_pusheval            rpp_obliterate_stack_to
cx_pushformat          rpp_replace_2_1_COMMON
cx_pushloop_for        runops_wrap
cx_pushloop_plain      scan_str
cx_pushsub             scan_word
cx_pushtry             skipspace_flags
cx_topblock            sv_free2
delete_eval_scope      sv_kill_backrefs
do_open_raw            sv_setpv_freshbuf
do_open6               sv_setsv_cow
emulate_cop_io         switch_argstack
get_re_arg             utf8_to_utf16_base
get_vtbl               xs_wrap
gimme_V                

Finally are the deprecated undocumented elements. Do not use any for new code; remove all occurrences of all of these from existing code.

get_no_modify  get_opargs  get_ppaddr  uvuni_to_utf8  

AUTHORS

The autodocumentation system was originally added to the Perl core by Benjamin Stuhl. Documentation is by whoever was kind enough to document their functions.

SEE ALSO

config.h, perlapi, perlapio, perlcall, perlclib, perlembed, perlfilter, perlguts, perlhacktips, perlinterp, perliol, perlmroapi, perlreapi, perlreguts, perlxs