3 perlintern - autogenerated documentation of purely B<internal>
8 This file is the autogenerated documentation of functions in the
9 Perl interpreter that are documented using Perl's internal documentation
10 format but are not marked as part of the Perl API. In other words,
11 B<they are not for use in extensions>!
14 =head1 Functions in file pad.h
21 Save the current pad in the given context block structure.
23 void CX_CURPAD_SAVE(struct context)
30 Access the SV at offset po in the saved current pad in the given
31 context block structure (can be used as an lvalue).
33 SV * CX_CURPAD_SV(struct context, PADOFFSET po)
40 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
42 SV * PAD_BASE_SV (PADLIST padlist, PADOFFSET po)
50 Clone the state variables associated with running and compiling pads.
52 void PAD_CLONE_VARS(PerlInterpreter *proto_perl \)
57 =item PAD_COMPNAME_FLAGS
59 Return the flags for the current compiling pad name
60 at offset C<po>. Assumes a valid slot entry.
62 U32 PAD_COMPNAME_FLAGS(PADOFFSET po)
67 =item PAD_COMPNAME_GEN
69 The generation number of the name at offset C<po> in the current
70 compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose.
72 STRLEN PAD_COMPNAME_GEN(PADOFFSET po)
77 =item PAD_COMPNAME_OURSTASH
79 Return the stash associated with an C<our> variable.
80 Assumes the slot entry is a valid C<our> lexical.
82 HV * PAD_COMPNAME_OURSTASH(PADOFFSET po)
89 Return the name of the current compiling pad name
90 at offset C<po>. Assumes a valid slot entry.
92 char * PAD_COMPNAME_PV(PADOFFSET po)
97 =item PAD_COMPNAME_TYPE
99 Return the type (stash) of the current compiling pad name at offset
100 C<po>. Must be a valid name. Returns null if not typed.
102 HV * PAD_COMPNAME_TYPE(PADOFFSET po)
111 void PAD_DUP(PADLIST dstpad, PADLIST srcpad, CLONE_PARAMS* param)
116 =item PAD_RESTORE_LOCAL
118 Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL()
120 void PAD_RESTORE_LOCAL(PAD *opad)
127 Save the current pad to the local variable opad, then make the
128 current pad equal to npad
130 void PAD_SAVE_LOCAL(PAD *opad, PAD *npad)
135 =item PAD_SAVE_SETNULLPAD
137 Save the current pad then set it to null.
139 void PAD_SAVE_SETNULLPAD()
146 Set the slot at offset C<po> in the current pad to C<sv>
148 SV * PAD_SETSV (PADOFFSET po, SV* sv)
155 Set the current pad to be pad C<n> in the padlist, saving
156 the previous current pad.
158 void PAD_SET_CUR (PADLIST padlist, I32 n)
165 Get the value at offset C<po> in the current pad
167 void PAD_SV (PADOFFSET po)
174 Lightweight and lvalue version of C<PAD_SV>.
175 Get or set the value at offset C<po> in the current pad.
176 Unlike C<PAD_SV>, does not print diagnostics with -DX.
177 For internal use only.
179 SV * PAD_SVl (PADOFFSET po)
186 Clear the pointed to pad value on scope exit. (ie the runtime action of 'my')
188 void SAVECLEARSV (SV **svp)
195 save PL_comppad and PL_curpad
208 Save a pad slot (used to restore after an iteration)
210 XXX DAPM it would make more sense to make the arg a PADOFFSET
211 void SAVEPADSV (PADOFFSET po)
219 =head1 Functions in file pp_ctl.c
226 Locate the CV corresponding to the currently executing sub or eval.
231 Found in file pp_ctl.c
236 =head1 Global Variables
242 When Perl is run in debugging mode, with the B<-d> switch, this SV is a
243 boolean which indicates whether subs are being single-stepped.
244 Single-stepping is automatically turned on after every step. This is the C
245 variable which corresponds to Perl's $DB::single variable. See
251 Found in file intrpvar.h
255 When Perl is run in debugging mode, with the B<-d> switch, this GV contains
256 the SV which holds the name of the sub being debugged. This is the C
257 variable which corresponds to Perl's $DB::sub variable. See
263 Found in file intrpvar.h
267 Trace variable used when Perl is run in debugging mode, with the B<-d>
268 switch. This is the C variable which corresponds to Perl's $DB::trace
269 variable. See C<PL_DBsingle>.
274 Found in file intrpvar.h
278 The C variable which corresponds to Perl's $^W warning variable.
283 Found in file intrpvar.h
287 The GV which was last used for a filehandle input operation. (C<< <FH> >>)
292 Found in file thrdvar.h
296 The output field separator - C<$,> in Perl space.
301 Found in file thrdvar.h
305 The input record separator - C<$/> in Perl space.
310 Found in file thrdvar.h
321 Returns C<TRUE> if given the name of a magical GV.
323 Currently only useful internally when determining if a GV should be
324 created even in rvalue contexts.
326 C<flags> is not used at present but available for future extension to
327 allow selecting particular classes of magical variable.
329 bool is_gv_magical(char *name, STRLEN len, U32 flags)
343 Function called by C<do_readline> to spawn a glob (or do the glob inside
344 perl on VMS). This code used to be inline, but now perl uses C<File::Glob>
345 this glob starter is only used by miniperl during the build process.
346 Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up.
348 PerlIO* start_glob(SV* pattern, IO *io)
356 =head1 Pad Data Structures
362 CV's can have CvPADLIST(cv) set to point to an AV.
364 For these purposes "forms" are a kind-of CV, eval""s are too (except they're
365 not callable at will and are always thrown away after the eval"" is done
368 XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad,
369 but that is really the callers pad (a slot of which is allocated by
372 The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items
373 is managed "manual" (mostly in pad.c) rather than normal av.c rules.
374 The items in the AV are not SVs as for a normal AV, but other AVs:
376 0'th Entry of the CvPADLIST is an AV which represents the "names" or rather
377 the "static type information" for lexicals.
379 The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that
380 depth of recursion into the CV.
381 The 0'th slot of a frame AV is an AV which is @_.
382 other entries are storage for variables and op targets.
385 C<PL_comppad_name> is set the the the names AV.
386 C<PL_comppad> is set the the frame AV for the frame CvDEPTH == 1.
387 C<PL_curpad> is set the body of the frame AV (i.e. AvARRAY(PL_comppad)).
389 During execution, C<PL_comppad> and C<PL_curpad> refer to the live
390 frame of the currently executing sub.
392 Iterating over the names AV iterates over all possible pad
393 items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having
394 &PL_sv_undef "names" (see pad_alloc()).
396 Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names.
397 The rest are op targets/GVs/constants which are statically allocated
398 or resolved at compile time. These don't have names by which they
399 can be looked up from Perl code at run time through eval"" like
400 my/our variables can be. Since they can't be looked up by "name"
401 but only by their index allocated at compile time (which is usually
402 in PL_op->op_targ), wasting a name SV for them doesn't make sense.
404 The SVs in the names AV have their PV being the name of the variable.
405 NV+1..IV inclusive is a range of cop_seq numbers for which the name is
406 valid. For typed lexicals name SV is SVt_PVMG and SvSTASH points at the
407 type. For C<our> lexicals, the type is SVt_PVGV, and GvSTASH points at the
408 stash of the associated global (so that duplicate C<our> delarations in the
409 same package can be detected). SvCUR is sometimes hijacked to
410 store the generation number during compilation.
412 If SvFAKE is set on the name SV then slot in the frame AVs are
413 a REFCNT'ed references to a lexical from "outside".
415 If the 'name' is '&' the the corresponding entry in frame AV
416 is a CV representing a possible closure.
417 (SvFAKE and name of '&' is not a meaningful combination currently but could
418 become so if C<my sub foo {}> is implemented.)
420 AV * CvPADLIST(CV *cv)
427 Clone a CV: make a new CV which points to the same code etc, but which
428 has a newly-created pad built by copying the prototype pad and capturing
431 CV* cv_clone(CV* proto)
438 dump the contents of a CV
440 void cv_dump(CV *cv, char *title)
447 Dump the contents of a padlist
449 void do_dump_pad(I32 level, PerlIO *file, PADLIST *padlist, int full)
456 "Introduce" my variables to visible status.
465 Add an anon code entry to the current compiling pad
467 PADOFFSET pad_add_anon(SV* sv, OPCODE op_type)
474 Create a new name in the current pad at the specified offset.
475 If C<typestash> is valid, the name is for a typed lexical; set the
476 name's stash to that value.
477 If C<ourstash> is valid, it's an our lexical, set the name's
478 GvSTASH to that value
480 Also, if the name is @.. or %.., create a new array or hash for that slot
482 If fake, it means we're cloning an existing entry
484 PADOFFSET pad_add_name(char *name, HV* typestash, HV* ourstash, bool clone)
491 Allocate a new my or tmp pad entry. For a my, simply push a null SV onto
492 the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards
493 for a slot which has no name and and no active value.
495 PADOFFSET pad_alloc(I32 optype, U32 tmptype)
500 =item pad_block_start
502 Update the pad compilation state variables on entry to a new block
504 void pad_block_start(int full)
511 Check for duplicate declarations: report any of:
512 * a my in the current scope with the same name;
513 * an our (anywhere in the pad) with the same name and the same stash
515 C<is_our> indicates that the name to check is an 'our' declaration
517 void pad_check_dup(char* name, bool is_our, HV* ourstash)
524 Find a named lexical anywhere in a chain of nested pads. Add fake entries
525 in the inner pads if it's found in an outer one. innercv is the CV *inside*
526 the chain of outer CVs to be searched. If newoff is non-null, this is a
527 run-time cloning: don't add fake entries, just find the lexical and add a
528 ref to it at newoff in the current pad.
530 PADOFFSET pad_findlex(char* name, PADOFFSET newoff, CV* innercv)
537 Given a lexical name, try to find its offset, first in the current pad,
538 or failing that, in the pads of any lexically enclosing subs (including
539 the complications introduced by eval). If the name is found in an outer pad,
540 then a fake entry is added to the current pad.
541 Returns the offset in the current pad, or NOT_IN_PAD on failure.
543 PADOFFSET pad_findmy(char* name)
548 =item pad_fixup_inner_anons
550 For any anon CVs in the pad, change CvOUTSIDE of that CV from
551 old_cv to new_cv if necessary.
553 void pad_fixup_inner_anons(PADLIST *padlist, CV *old_cv, CV *new_cv)
560 Free the SV at offet po in the current pad.
562 void pad_free(PADOFFSET po)
569 Cleanup at end of scope during compilation: set the max seq number for
570 lexicals in this scope and warn of any lexicals that never got introduced.
579 Create a new compiling padlist, saving and updating the various global
580 vars at the same time as creating the pad itself. The following flags
581 can be OR'ed together:
583 padnew_CLONE this pad is for a cloned CV
584 padnew_SAVE save old globals
585 padnew_SAVESUB also save extra stuff for start of sub
587 PADLIST* pad_new(padnew_flags flags)
594 Push a new pad frame onto the padlist, unless there's already a pad at
595 this depth, in which case don't bother creating a new one.
596 If has_args is true, give the new pad an @_ in slot zero.
598 void pad_push(PADLIST *padlist, int depth, int has_args)
605 Mark all the current temporaries for reuse
614 Set the entry at offset po in the current pad to sv.
615 Use the macro PAD_SETSV() rather than calling this function directly.
617 void pad_setsv(PADOFFSET po, SV* sv)
624 Abandon the tmp in the current pad at offset po and replace with a
627 void pad_swipe(PADOFFSET po, bool refadjust)
634 Tidy up a pad after we've finished compiling it:
635 * remove most stuff from the pads of anonsub prototypes;
639 void pad_tidy(padtidy_type type)
646 Free the padlist associated with a CV.
647 If parts of it happen to be current, we null the relevant
648 PL_*pad* global vars so that we don't have any dangling references left.
649 We also repoint the CvOUTSIDE of any about-to-be-orphaned
650 inner subs to the outer of this cv.
652 void pad_undef(CV* cv)
660 =head1 Stack Manipulation Macros
666 Declare Just C<SP>. This is actually identical to C<dSP>, and declares
667 a local copy of perl's stack pointer, available via the C<SP> macro.
668 See C<SP>. (Available for backward source code compatibility with the
669 old (Perl 5.005) thread model.)
678 True if this op will be the return value of an lvalue subroutine
686 =head1 SV Manipulation Functions
692 Print appropriate "Use of uninitialized variable" warning
701 Given a chunk of memory, link it to the head of the list of arenas,
702 and split it into a list of free SVs.
704 void sv_add_arena(char* ptr, U32 size, U32 flags)
711 Decrement the refcnt of each remaining SV, possibly triggering a
712 cleanup. This function may have to be called multiple times to free
713 SVs which are in complex self-referential hierarchies.
722 Attempt to destroy all objects not yet freed
731 Deallocate the memory used by all arenas. Note that all the individual SV
732 heads and bodies within the arenas must already have been freed.
734 void sv_free_arenas()
744 The autodocumentation system was originally added to the Perl core by
745 Benjamin Stuhl. Documentation is by whoever was kind enough to
746 document their functions.
750 perlguts(1), perlapi(1)