3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2004, by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * 'Mercy!' cried Gandalf. 'If the giving of information is to be the cure
13 * of your inquisitiveness, I shall spend all the rest of my days answering
14 * you. What more do you want to know?'
15 * 'The names of all the stars, and of all living things, and the whole
16 * history of Middle-earth and Over-heaven and of the Sundering Seas,'
23 A GV is a structure which corresponds to to a Perl typeglob, ie *foo.
24 It is a structure that holds a pointer to a scalar, an array, a hash etc,
25 corresponding to $foo, @foo, %foo.
27 GVs are usually found as values in stashes (symbol table hashes) where
28 Perl stores its global variables.
38 Perl_gv_AVadd(pTHX_ register GV *gv)
40 if (!gv || SvTYPE((SV*)gv) != SVt_PVGV)
41 Perl_croak(aTHX_ "Bad symbol for array");
48 Perl_gv_HVadd(pTHX_ register GV *gv)
50 if (!gv || SvTYPE((SV*)gv) != SVt_PVGV)
51 Perl_croak(aTHX_ "Bad symbol for hash");
58 Perl_gv_IOadd(pTHX_ register GV *gv)
60 if (!gv || SvTYPE((SV*)gv) != SVt_PVGV)
61 Perl_croak(aTHX_ "Bad symbol for filehandle");
63 #ifdef GV_UNIQUE_CHECK
65 Perl_croak(aTHX_ "Bad symbol for filehandle (GV is unique)");
74 Perl_gv_fetchfile(pTHX_ const char *name)
84 tmplen = strlen(name) + 2;
85 if (tmplen < sizeof smallbuf)
88 New(603, tmpbuf, tmplen + 1, char);
89 /* This is where the debugger's %{"::_<$filename"} hash is created */
92 strcpy(tmpbuf + 2, name);
93 gv = *(GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, TRUE);
95 gv_init(gv, PL_defstash, tmpbuf, tmplen, FALSE);
96 sv_setpv(GvSV(gv), name);
98 hv_magic(GvHVn(gv_AVadd(gv)), Nullgv, PERL_MAGIC_dbfile);
100 if (tmpbuf != smallbuf)
106 Perl_gv_init(pTHX_ GV *gv, HV *stash, const char *name, STRLEN len, int multi)
109 bool doproto = SvTYPE(gv) > SVt_NULL;
110 char *proto = (doproto && SvPOK(gv)) ? SvPVX(gv) : NULL;
112 sv_upgrade((SV*)gv, SVt_PVGV);
121 Newz(602, gp, 1, GP);
122 GvGP(gv) = gp_ref(gp);
123 GvSV(gv) = NEWSV(72,0);
124 GvLINE(gv) = CopLINE(PL_curcop);
125 GvFILE(gv) = CopFILE(PL_curcop) ? CopFILE(PL_curcop) : "";
128 sv_magic((SV*)gv, (SV*)gv, PERL_MAGIC_glob, Nullch, 0);
129 GvSTASH(gv) = (HV*)SvREFCNT_inc(stash);
130 GvNAME(gv) = savepvn(name, len);
132 if (multi || doproto) /* doproto means it _was_ mentioned */
134 if (doproto) { /* Replicate part of newSUB here. */
137 /* XXX unsafe for threads if eval_owner isn't held */
138 start_subparse(0,0); /* Create CV in compcv. */
139 GvCV(gv) = PL_compcv;
144 CvFILE_set_from_cop(GvCV(gv), PL_curcop);
145 CvSTASH(GvCV(gv)) = PL_curstash;
147 sv_setpv((SV*)GvCV(gv), proto);
154 S_gv_init_sv(pTHX_ GV *gv, I32 sv_type)
170 =for apidoc gv_fetchmeth
172 Returns the glob with the given C<name> and a defined subroutine or
173 C<NULL>. The glob lives in the given C<stash>, or in the stashes
174 accessible via @ISA and UNIVERSAL::.
176 The argument C<level> should be either 0 or -1. If C<level==0>, as a
177 side-effect creates a glob with the given C<name> in the given C<stash>
178 which in the case of success contains an alias for the subroutine, and sets
179 up caching info for this glob. Similarly for all the searched stashes.
181 This function grants C<"SUPER"> token as a postfix of the stash name. The
182 GV returned from C<gv_fetchmeth> may be a method cache entry, which is not
183 visible to Perl code. So when calling C<call_sv>, you should not use
184 the GV directly; instead, you should use the method's CV, which can be
185 obtained from the GV with the C<GvCV> macro.
191 Perl_gv_fetchmeth(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
199 /* UNIVERSAL methods should be callable without a stash */
201 level = -1; /* probably appropriate */
202 if(!(stash = gv_stashpvn("UNIVERSAL", 9, FALSE)))
208 "Can't use anonymous symbol table for method lookup");
210 if ((level > 100) || (level < -100))
211 Perl_croak(aTHX_ "Recursive inheritance detected while looking for method '%s' in package '%s'",
212 name, HvNAME(stash));
214 DEBUG_o( Perl_deb(aTHX_ "Looking for method %s in package %s\n",name,HvNAME(stash)) );
216 gvp = (GV**)hv_fetch(stash, name, len, (level >= 0));
221 if (SvTYPE(topgv) != SVt_PVGV)
222 gv_init(topgv, stash, name, len, TRUE);
223 if ((cv = GvCV(topgv))) {
224 /* If genuine method or valid cache entry, use it */
225 if (!GvCVGEN(topgv) || GvCVGEN(topgv) == PL_sub_generation)
227 /* Stale cached entry: junk it */
229 GvCV(topgv) = cv = Nullcv;
232 else if (GvCVGEN(topgv) == PL_sub_generation)
233 return 0; /* cache indicates sub doesn't exist */
236 gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
237 av = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : Nullav;
239 /* create and re-create @.*::SUPER::ISA on demand */
240 if (!av || !SvMAGIC(av)) {
241 char* packname = HvNAME(stash);
242 STRLEN packlen = strlen(packname);
244 if (packlen >= 7 && strEQ(packname + packlen - 7, "::SUPER")) {
248 basestash = gv_stashpvn(packname, packlen, TRUE);
249 gvp = (GV**)hv_fetch(basestash, "ISA", 3, FALSE);
250 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
251 gvp = (GV**)hv_fetch(stash, "ISA", 3, TRUE);
252 if (!gvp || !(gv = *gvp))
253 Perl_croak(aTHX_ "Cannot create %s::ISA", HvNAME(stash));
254 if (SvTYPE(gv) != SVt_PVGV)
255 gv_init(gv, stash, "ISA", 3, TRUE);
256 SvREFCNT_dec(GvAV(gv));
257 GvAV(gv) = (AV*)SvREFCNT_inc(av);
263 SV** svp = AvARRAY(av);
264 /* NOTE: No support for tied ISA */
265 I32 items = AvFILLp(av) + 1;
268 HV* basestash = gv_stashsv(sv, FALSE);
270 if (ckWARN(WARN_MISC))
271 Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
275 gv = gv_fetchmeth(basestash, name, len,
276 (level >= 0) ? level + 1 : level - 1);
282 /* if at top level, try UNIVERSAL */
284 if (level == 0 || level == -1) {
287 if ((lastchance = gv_stashpvn("UNIVERSAL", 9, FALSE))) {
288 if ((gv = gv_fetchmeth(lastchance, name, len,
289 (level >= 0) ? level + 1 : level - 1)))
293 * Cache method in topgv if:
294 * 1. topgv has no synonyms (else inheritance crosses wires)
295 * 2. method isn't a stub (else AUTOLOAD fails spectacularly)
298 GvREFCNT(topgv) == 1 &&
300 (CvROOT(cv) || CvXSUB(cv)))
302 if ((cv = GvCV(topgv)))
304 GvCV(topgv) = (CV*)SvREFCNT_inc(GvCV(gv));
305 GvCVGEN(topgv) = PL_sub_generation;
309 else if (topgv && GvREFCNT(topgv) == 1) {
310 /* cache the fact that the method is not defined */
311 GvCVGEN(topgv) = PL_sub_generation;
320 =for apidoc gv_fetchmeth_autoload
322 Same as gv_fetchmeth(), but looks for autoloaded subroutines too.
323 Returns a glob for the subroutine.
325 For an autoloaded subroutine without a GV, will create a GV even
326 if C<level < 0>. For an autoloaded subroutine without a stub, GvCV()
327 of the result may be zero.
333 Perl_gv_fetchmeth_autoload(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
335 GV *gv = gv_fetchmeth(stash, name, len, level);
338 char autoload[] = "AUTOLOAD";
339 STRLEN autolen = sizeof(autoload)-1;
344 return Nullgv; /* UNIVERSAL::AUTOLOAD could cause trouble */
345 if (len == autolen && strnEQ(name, autoload, autolen))
347 if (!(gv = gv_fetchmeth(stash, autoload, autolen, FALSE)))
350 if (!(CvROOT(cv) || CvXSUB(cv)))
352 /* Have an autoload */
353 if (level < 0) /* Cannot do without a stub */
354 gv_fetchmeth(stash, name, len, 0);
355 gvp = (GV**)hv_fetch(stash, name, len, (level >= 0));
364 =for apidoc gv_fetchmethod
366 See L<gv_fetchmethod_autoload>.
372 Perl_gv_fetchmethod(pTHX_ HV *stash, const char *name)
374 return gv_fetchmethod_autoload(stash, name, TRUE);
378 =for apidoc gv_fetchmethod_autoload
380 Returns the glob which contains the subroutine to call to invoke the method
381 on the C<stash>. In fact in the presence of autoloading this may be the
382 glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD is
385 The third parameter of C<gv_fetchmethod_autoload> determines whether
386 AUTOLOAD lookup is performed if the given method is not present: non-zero
387 means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD.
388 Calling C<gv_fetchmethod> is equivalent to calling C<gv_fetchmethod_autoload>
389 with a non-zero C<autoload> parameter.
391 These functions grant C<"SUPER"> token as a prefix of the method name. Note
392 that if you want to keep the returned glob for a long time, you need to
393 check for it being "AUTOLOAD", since at the later time the call may load a
394 different subroutine due to $AUTOLOAD changing its value. Use the glob
395 created via a side effect to do this.
397 These functions have the same side-effects and as C<gv_fetchmeth> with
398 C<level==0>. C<name> should be writable if contains C<':'> or C<'
399 ''>. The warning against passing the GV returned by C<gv_fetchmeth> to
400 C<call_sv> apply equally to these functions.
406 Perl_gv_fetchmethod_autoload(pTHX_ HV *stash, const char *name, I32 autoload)
408 register const char *nend;
409 const char *nsplit = 0;
413 if (stash && SvTYPE(stash) < SVt_PVHV)
416 for (nend = name; *nend; nend++) {
419 else if (*nend == ':' && *(nend + 1) == ':')
423 const char *origname = name;
427 if ((nsplit - origname) == 5 && strnEQ(origname, "SUPER", 5)) {
428 /* ->SUPER::method should really be looked up in original stash */
429 SV *tmpstr = sv_2mortal(Perl_newSVpvf(aTHX_ "%s::SUPER",
430 CopSTASHPV(PL_curcop)));
431 /* __PACKAGE__::SUPER stash should be autovivified */
432 stash = gv_stashpvn(SvPVX(tmpstr), SvCUR(tmpstr), TRUE);
433 DEBUG_o( Perl_deb(aTHX_ "Treating %s as %s::%s\n",
434 origname, HvNAME(stash), name) );
437 /* don't autovifify if ->NoSuchStash::method */
438 stash = gv_stashpvn(origname, nsplit - origname, FALSE);
440 /* however, explicit calls to Pkg::SUPER::method may
441 happen, and may require autovivification to work */
442 if (!stash && (nsplit - origname) >= 7 &&
443 strnEQ(nsplit - 7, "::SUPER", 7) &&
444 gv_stashpvn(origname, nsplit - origname - 7, FALSE))
445 stash = gv_stashpvn(origname, nsplit - origname, TRUE);
450 gv = gv_fetchmeth(stash, name, nend - name, 0);
452 if (strEQ(name,"import") || strEQ(name,"unimport"))
453 gv = (GV*)&PL_sv_yes;
455 gv = gv_autoload4(ostash, name, nend - name, TRUE);
459 if (!CvROOT(cv) && !CvXSUB(cv)) {
467 if (GvCV(stubgv) != cv) /* orphaned import */
470 autogv = gv_autoload4(GvSTASH(stubgv),
471 GvNAME(stubgv), GvNAMELEN(stubgv), TRUE);
481 Perl_gv_autoload4(pTHX_ HV *stash, const char *name, STRLEN len, I32 method)
483 char autoload[] = "AUTOLOAD";
484 STRLEN autolen = sizeof(autoload)-1;
492 if (len == autolen && strnEQ(name, autoload, autolen))
495 if (SvTYPE(stash) < SVt_PVHV) {
496 packname = SvPV_nolen((SV*)stash);
500 packname = HvNAME(stash);
503 if (!(gv = gv_fetchmeth(stash, autoload, autolen, FALSE)))
507 if (!(CvROOT(cv) || CvXSUB(cv)))
511 * Inheriting AUTOLOAD for non-methods works ... for now.
513 if (ckWARN2(WARN_DEPRECATED, WARN_SYNTAX) && !method &&
514 (GvCVGEN(gv) || GvSTASH(gv) != stash))
515 Perl_warner(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
516 "Use of inherited AUTOLOAD for non-method %s::%.*s() is deprecated",
517 packname, (int)len, name);
520 /* rather than lookup/init $AUTOLOAD here
521 * only to have the XSUB do another lookup for $AUTOLOAD
522 * and split that value on the last '::',
523 * pass along the same data via some unused fields in the CV
526 SvPVX(cv) = (char *)name; /* cast to lose constness warning */
532 * Given &FOO::AUTOLOAD, set $FOO::AUTOLOAD to desired function name.
533 * The subroutine's original name may not be "AUTOLOAD", so we don't
534 * use that, but for lack of anything better we will use the sub's
535 * original package to look up $AUTOLOAD.
537 varstash = GvSTASH(CvGV(cv));
538 vargv = *(GV**)hv_fetch(varstash, autoload, autolen, TRUE);
542 gv_init(vargv, varstash, autoload, autolen, FALSE);
545 sv_setpv(varsv, packname);
546 sv_catpvn(varsv, "::", 2);
547 sv_catpvn(varsv, name, len);
548 SvTAINTED_off(varsv);
552 /* The "gv" parameter should be the glob known to Perl code as *!
553 * The scalar must already have been magicalized.
556 S_require_errno(pTHX_ GV *gv)
558 HV* stash = gv_stashpvn("Errno",5,FALSE);
560 if (!stash || !(gv_fetchmethod(stash, "TIEHASH"))) {
564 save_scalar(gv); /* keep the value of $! */
565 Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT,
566 newSVpvn("Errno",5), Nullsv);
569 stash = gv_stashpvn("Errno",5,FALSE);
570 if (!stash || !(gv_fetchmethod(stash, "TIEHASH")))
571 Perl_croak(aTHX_ "Can't use %%! because Errno.pm is not available");
576 =for apidoc gv_stashpv
578 Returns a pointer to the stash for a specified package. C<name> should
579 be a valid UTF-8 string and must be null-terminated. If C<create> is set
580 then the package will be created if it does not already exist. If C<create>
581 is not set and the package does not exist then NULL is returned.
587 Perl_gv_stashpv(pTHX_ const char *name, I32 create)
589 return gv_stashpvn(name, strlen(name), create);
593 =for apidoc gv_stashpvn
595 Returns a pointer to the stash for a specified package. C<name> should
596 be a valid UTF-8 string. The C<namelen> parameter indicates the length of
597 the C<name>, in bytes. If C<create> is set then the package will be
598 created if it does not already exist. If C<create> is not set and the
599 package does not exist then NULL is returned.
605 Perl_gv_stashpvn(pTHX_ const char *name, U32 namelen, I32 create)
612 if (namelen + 3 < sizeof smallbuf)
615 New(606, tmpbuf, namelen + 3, char);
616 Copy(name,tmpbuf,namelen,char);
617 tmpbuf[namelen++] = ':';
618 tmpbuf[namelen++] = ':';
619 tmpbuf[namelen] = '\0';
620 tmpgv = gv_fetchpv(tmpbuf, create, SVt_PVHV);
621 if (tmpbuf != smallbuf)
626 GvHV(tmpgv) = newHV();
629 HvNAME(stash) = savepv(name);
634 =for apidoc gv_stashsv
636 Returns a pointer to the stash for a specified package, which must be a
637 valid UTF-8 string. See C<gv_stashpv>.
643 Perl_gv_stashsv(pTHX_ SV *sv, I32 create)
648 return gv_stashpvn(ptr, len, create);
653 Perl_gv_fetchpv(pTHX_ const char *nambeg, I32 add, I32 sv_type)
655 register const char *name = nambeg;
659 register const char *namend;
662 if (*name == '*' && isALPHA(name[1])) /* accidental stringify on a GV? */
665 for (namend = name; *namend; namend++) {
666 if ((*namend == ':' && namend[1] == ':')
667 || (*namend == '\'' && namend[1]))
671 if (!stash || !SvREFCNT(stash)) /* symbol table under destruction */
679 if (len + 3 < sizeof (smallbuf))
682 New(601, tmpbuf, len+3, char);
683 Copy(name, tmpbuf, len, char);
687 gvp = (GV**)hv_fetch(stash,tmpbuf,len,add);
688 gv = gvp ? *gvp : Nullgv;
689 if (gv && gv != (GV*)&PL_sv_undef) {
690 if (SvTYPE(gv) != SVt_PVGV)
691 gv_init(gv, stash, tmpbuf, len, (add & GV_ADDMULTI));
695 if (tmpbuf != smallbuf)
697 if (!gv || gv == (GV*)&PL_sv_undef)
700 if (!(stash = GvHV(gv)))
701 stash = GvHV(gv) = newHV();
704 HvNAME(stash) = savepvn(nambeg, namend - nambeg);
712 return gv ? gv : (GV*)*hv_fetch(PL_defstash, "main::", 6, TRUE);
717 /* No stash in name, so see how we can default */
720 if (isIDFIRST_lazy(name)) {
723 if (isUPPER(*name)) {
724 if (*name == 'S' && (
725 strEQ(name, "SIG") ||
726 strEQ(name, "STDIN") ||
727 strEQ(name, "STDOUT") ||
728 strEQ(name, "STDERR")))
730 else if (*name == 'I' && strEQ(name, "INC"))
732 else if (*name == 'E' && strEQ(name, "ENV"))
734 else if (*name == 'A' && (
735 strEQ(name, "ARGV") ||
736 strEQ(name, "ARGVOUT")))
739 else if (*name == '_' && !name[1])
744 else if (IN_PERL_COMPILETIME) {
746 if (add && (PL_hints & HINT_STRICT_VARS) &&
747 sv_type != SVt_PVCV &&
748 sv_type != SVt_PVGV &&
749 sv_type != SVt_PVFM &&
750 sv_type != SVt_PVIO &&
751 !(len == 1 && sv_type == SVt_PV &&
752 (*name == 'a' || *name == 'b')) )
754 gvp = (GV**)hv_fetch(stash,name,len,0);
756 *gvp == (GV*)&PL_sv_undef ||
757 SvTYPE(*gvp) != SVt_PVGV)
761 else if ((sv_type == SVt_PV && !GvIMPORTED_SV(*gvp)) ||
762 (sv_type == SVt_PVAV && !GvIMPORTED_AV(*gvp)) ||
763 (sv_type == SVt_PVHV && !GvIMPORTED_HV(*gvp)) )
765 Perl_warn(aTHX_ "Variable \"%c%s\" is not imported",
766 sv_type == SVt_PVAV ? '@' :
767 sv_type == SVt_PVHV ? '%' : '$',
770 Perl_warn(aTHX_ "\t(Did you mean &%s instead?)\n", name);
776 stash = CopSTASH(PL_curcop);
782 /* By this point we should have a stash and a name */
786 register SV *err = Perl_mess(aTHX_
787 "Global symbol \"%s%s\" requires explicit package name",
788 (sv_type == SVt_PV ? "$"
789 : sv_type == SVt_PVAV ? "@"
790 : sv_type == SVt_PVHV ? "%"
792 if (USE_UTF8_IN_NAMES)
795 stash = GvHV(gv_fetchpv("<none>::", GV_ADDMULTI, SVt_PVHV));
801 if (!SvREFCNT(stash)) /* symbol table under destruction */
804 gvp = (GV**)hv_fetch(stash,name,len,add);
805 if (!gvp || *gvp == (GV*)&PL_sv_undef)
808 if (SvTYPE(gv) == SVt_PVGV) {
811 gv_init_sv(gv, sv_type);
812 if (*name=='!' && sv_type == SVt_PVHV && len==1)
816 } else if (add & GV_NOINIT) {
820 /* Adding a new symbol */
822 if (add & GV_ADDWARN && ckWARN_d(WARN_INTERNAL))
823 Perl_warner(aTHX_ packWARN(WARN_INTERNAL), "Had to create %s unexpectedly", nambeg);
824 gv_init(gv, stash, name, len, add & GV_ADDMULTI);
825 gv_init_sv(gv, sv_type);
827 if (isALPHA(name[0]) && ! (isLEXWARN_on ? ckWARN(WARN_ONCE)
828 : (PL_dowarn & G_WARN_ON ) ) )
831 /* set up magic where warranted */
834 if (strEQ(name, "ARGV")) {
835 IoFLAGS(GvIOn(gv)) |= IOf_ARGV|IOf_START;
839 if (strnEQ(name, "EXPORT", 6))
843 if (strEQ(name, "ISA")) {
846 sv_magic((SV*)av, (SV*)gv, PERL_MAGIC_isa, Nullch, 0);
847 /* NOTE: No support for tied ISA */
848 if ((add & GV_ADDMULTI) && strEQ(nambeg,"AnyDBM_File::ISA")
849 && AvFILLp(av) == -1)
852 av_push(av, newSVpvn(pname = "NDBM_File",9));
853 gv_stashpvn(pname, 9, TRUE);
854 av_push(av, newSVpvn(pname = "DB_File",7));
855 gv_stashpvn(pname, 7, TRUE);
856 av_push(av, newSVpvn(pname = "GDBM_File",9));
857 gv_stashpvn(pname, 9, TRUE);
858 av_push(av, newSVpvn(pname = "SDBM_File",9));
859 gv_stashpvn(pname, 9, TRUE);
860 av_push(av, newSVpvn(pname = "ODBM_File",9));
861 gv_stashpvn(pname, 9, TRUE);
866 if (strEQ(name, "OVERLOAD")) {
869 hv_magic(hv, Nullgv, PERL_MAGIC_overload);
873 if (strEQ(name, "SIG")) {
877 Newz(73, PL_psig_ptr, SIG_SIZE, SV*);
878 Newz(73, PL_psig_name, SIG_SIZE, SV*);
879 Newz(73, PL_psig_pend, SIG_SIZE, int);
883 hv_magic(hv, Nullgv, PERL_MAGIC_sig);
884 for (i = 1; i < SIG_SIZE; i++) {
886 init = hv_fetch(hv, PL_sig_name[i], strlen(PL_sig_name[i]), 1);
888 sv_setsv(*init, &PL_sv_undef);
896 if (strEQ(name, "VERSION"))
905 sv_type == SVt_PVAV ||
906 sv_type == SVt_PVHV ||
907 sv_type == SVt_PVCV ||
908 sv_type == SVt_PVFM ||
911 PL_sawampersand = TRUE;
917 sv_setpv(GvSV(gv),PL_chopset);
923 #ifdef COMPLEX_STATUS
924 (void)SvUPGRADE(GvSV(gv), SVt_PVLV);
932 /* If %! has been used, automatically load Errno.pm.
933 The require will itself set errno, so in order to
934 preserve its value we have to set up the magic
935 now (rather than going to magicalize)
938 sv_magic(GvSV(gv), (SV*)gv, PERL_MAGIC_sv, name, len);
940 if (sv_type == SVt_PVHV)
949 sv_magic((SV*)av, Nullsv, PERL_MAGIC_regdata, Nullch, 0);
954 if (len == 1 && sv_type == SVt_PV && ckWARN2(WARN_DEPRECATED, WARN_SYNTAX))
955 Perl_warner(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
956 "$* is no longer supported");
959 if (len == 1 && sv_type == SVt_PV && ckWARN2(WARN_DEPRECATED, WARN_SYNTAX))
960 Perl_warner(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
961 "Use of $# is deprecated");
976 case '\001': /* $^A */
977 case '\003': /* $^C */
978 case '\004': /* $^D */
979 case '\006': /* $^F */
980 case '\010': /* $^H */
981 case '\011': /* $^I, NOT \t in EBCDIC */
982 case '\016': /* $^N */
983 case '\020': /* $^P */
990 sv_setiv(GvSV(gv), (IV)(IoFLAGS(GvIOp(PL_defoutgv)) & IOf_FLUSH) != 0);
992 case '\005': /* $^E && $^ENCODING */
993 if (len > 1 && strNE(name, "\005NCODING"))
997 case '\017': /* $^O & $^OPEN */
998 if (len > 1 && strNE(name, "\017PEN"))
1001 case '\023': /* $^S */
1005 case '\024': /* $^T, ${^TAINT} */
1008 else if (strEQ(name, "\024AINT"))
1013 if (len > 1 && strNE(name, "\025NICODE"))
1017 case '\027': /* $^W & $^WARNING_BITS */
1019 && strNE(name, "\027ARNING_BITS")
1029 sv_magic((SV*)av, (SV*)av, PERL_MAGIC_regdata, Nullch, 0);
1042 /* ensures variable is only digits */
1043 /* ${"1foo"} fails this test (and is thus writeable) */
1044 /* added by japhy, but borrowed from is_gv_magical */
1047 const char *end = name + len;
1048 while (--end > name) {
1049 if (!isDIGIT(*end)) return gv;
1054 SvREADONLY_on(GvSV(gv));
1056 sv_magic(GvSV(gv), (SV*)gv, PERL_MAGIC_sv, name, len);
1059 case '\014': /* $^L */
1062 sv_setpv(GvSV(gv),"\f");
1063 PL_formfeed = GvSV(gv);
1068 sv_setpv(GvSV(gv),"\034");
1073 if (!sv_derived_from(PL_patchlevel, "version"))
1074 (void *)upg_version(PL_patchlevel);
1075 GvSV(gv) = vnumify(PL_patchlevel);
1076 SvREADONLY_on(GvSV(gv));
1080 case '\026': /* $^V */
1083 GvSV(gv) = new_version(PL_patchlevel);
1084 SvREADONLY_on(GvSV(gv));
1093 Perl_gv_fullname4(pTHX_ SV *sv, GV *gv, const char *prefix, bool keepmain)
1096 HV *hv = GvSTASH(gv);
1101 sv_setpv(sv, prefix ? prefix : "");
1107 if (keepmain || strNE(name, "main")) {
1109 sv_catpvn(sv,"::", 2);
1111 sv_catpvn(sv,GvNAME(gv),GvNAMELEN(gv));
1115 Perl_gv_fullname3(pTHX_ SV *sv, GV *gv, const char *prefix)
1117 gv_fullname4(sv, gv, prefix, TRUE);
1121 Perl_gv_efullname4(pTHX_ SV *sv, GV *gv, const char *prefix, bool keepmain)
1123 GV *egv = GvEGV(gv);
1126 gv_fullname4(sv, egv, prefix, keepmain);
1130 Perl_gv_efullname3(pTHX_ SV *sv, GV *gv, const char *prefix)
1132 gv_efullname4(sv, gv, prefix, TRUE);
1135 /* XXX compatibility with versions <= 5.003. */
1137 Perl_gv_fullname(pTHX_ SV *sv, GV *gv)
1139 gv_fullname3(sv, gv, sv == (SV*)gv ? "*" : "");
1142 /* XXX compatibility with versions <= 5.003. */
1144 Perl_gv_efullname(pTHX_ SV *sv, GV *gv)
1146 gv_efullname3(sv, gv, sv == (SV*)gv ? "*" : "");
1155 io = (IO*)NEWSV(0,0);
1156 sv_upgrade((SV *)io,SVt_PVIO);
1159 /* Clear the stashcache because a new IO could overrule a
1161 hv_clear(PL_stashcache);
1162 iogv = gv_fetchpv("FileHandle::", FALSE, SVt_PVHV);
1163 /* unless exists($main::{FileHandle}) and defined(%main::FileHandle::) */
1164 if (!(iogv && GvHV(iogv) && HvARRAY(GvHV(iogv))))
1165 iogv = gv_fetchpv("IO::Handle::", TRUE, SVt_PVHV);
1166 SvSTASH(io) = (HV*)SvREFCNT_inc(GvHV(iogv));
1171 Perl_gv_check(pTHX_ HV *stash)
1178 if (!HvARRAY(stash))
1180 for (i = 0; i <= (I32) HvMAX(stash); i++) {
1181 for (entry = HvARRAY(stash)[i]; entry; entry = HeNEXT(entry)) {
1182 if (HeKEY(entry)[HeKLEN(entry)-1] == ':' &&
1183 (gv = (GV*)HeVAL(entry)) && isGV(gv) && (hv = GvHV(gv)))
1185 if (hv != PL_defstash && hv != stash)
1186 gv_check(hv); /* nested package */
1188 else if (isALPHA(*HeKEY(entry))) {
1190 gv = (GV*)HeVAL(entry);
1191 if (SvTYPE(gv) != SVt_PVGV || GvMULTI(gv))
1194 /* performance hack: if filename is absolute and it's a standard
1195 * module, don't bother warning */
1197 && PERL_FILE_IS_ABSOLUTE(file)
1198 #ifdef MACOS_TRADITIONAL
1199 && (instr(file, ":lib:")
1201 && (instr(file, "/lib/")
1203 || instr(file, ".pm")))
1207 CopLINE_set(PL_curcop, GvLINE(gv));
1209 CopFILE(PL_curcop) = file; /* set for warning */
1211 CopFILEGV(PL_curcop) = gv_fetchfile(file);
1213 Perl_warner(aTHX_ packWARN(WARN_ONCE),
1214 "Name \"%s::%s\" used only once: possible typo",
1215 HvNAME(stash), GvNAME(gv));
1222 Perl_newGVgen(pTHX_ char *pack)
1224 return gv_fetchpv(Perl_form(aTHX_ "%s::_GEN_%ld", pack, (long)PL_gensym++),
1228 /* hopefully this is only called on local symbol table entries */
1231 Perl_gp_ref(pTHX_ GP *gp)
1238 /* multi-named GPs cannot be used for method cache */
1239 SvREFCNT_dec(gp->gp_cv);
1244 /* Adding a new name to a subroutine invalidates method cache */
1245 PL_sub_generation++;
1252 Perl_gp_free(pTHX_ GV *gv)
1256 if (!gv || !(gp = GvGP(gv)))
1258 if (gp->gp_refcnt == 0) {
1259 if (ckWARN_d(WARN_INTERNAL))
1260 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
1261 "Attempt to free unreferenced glob pointers"
1262 pTHX__FORMAT pTHX__VALUE);
1266 /* Deleting the name of a subroutine invalidates method cache */
1267 PL_sub_generation++;
1269 if (--gp->gp_refcnt > 0) {
1270 if (gp->gp_egv == gv)
1275 if (gp->gp_sv) SvREFCNT_dec(gp->gp_sv);
1276 if (gp->gp_av) SvREFCNT_dec(gp->gp_av);
1278 if (PL_stashcache && HvNAME(gp->gp_hv))
1279 hv_delete(PL_stashcache,
1280 HvNAME(gp->gp_hv), strlen(HvNAME(gp->gp_hv)),
1282 SvREFCNT_dec(gp->gp_hv);
1284 if (gp->gp_io) SvREFCNT_dec(gp->gp_io);
1285 if (gp->gp_cv) SvREFCNT_dec(gp->gp_cv);
1286 if (gp->gp_form) SvREFCNT_dec(gp->gp_form);
1293 Perl_magic_freeovrld(pTHX_ SV *sv, MAGIC *mg)
1295 AMT *amtp = (AMT*)mg->mg_ptr;
1296 if (amtp && AMT_AMAGIC(amtp)) {
1298 for (i = 1; i < NofAMmeth; i++) {
1299 CV *cv = amtp->table[i];
1301 SvREFCNT_dec((SV *) cv);
1302 amtp->table[i] = Nullcv;
1309 /* Updates and caches the CV's */
1312 Perl_Gv_AMupdate(pTHX_ HV *stash)
1316 MAGIC* mg=mg_find((SV*)stash, PERL_MAGIC_overload_table);
1317 AMT *amtp = (mg) ? (AMT*)mg->mg_ptr: (AMT *) NULL;
1320 if (mg && amtp->was_ok_am == PL_amagic_generation
1321 && amtp->was_ok_sub == PL_sub_generation)
1322 return (bool)AMT_OVERLOADED(amtp);
1323 sv_unmagic((SV*)stash, PERL_MAGIC_overload_table);
1325 DEBUG_o( Perl_deb(aTHX_ "Recalcing overload magic in package %s\n",HvNAME(stash)) );
1328 amt.was_ok_am = PL_amagic_generation;
1329 amt.was_ok_sub = PL_sub_generation;
1330 amt.fallback = AMGfallNO;
1334 int filled = 0, have_ovl = 0;
1338 /* Work with "fallback" key, which we assume to be first in PL_AMG_names */
1340 /* Try to find via inheritance. */
1341 gv = gv_fetchmeth(stash, PL_AMG_names[0], 2, -1);
1346 lim = DESTROY_amg; /* Skip overloading entries. */
1347 else if (SvTRUE(sv))
1348 amt.fallback=AMGfallYES;
1350 amt.fallback=AMGfallNEVER;
1352 for (i = 1; i < lim; i++)
1353 amt.table[i] = Nullcv;
1354 for (; i < NofAMmeth; i++) {
1355 char *cooky = (char*)PL_AMG_names[i];
1356 /* Human-readable form, for debugging: */
1357 char *cp = (i >= DESTROY_amg ? cooky : AMG_id2name(i));
1358 STRLEN l = strlen(cooky);
1360 DEBUG_o( Perl_deb(aTHX_ "Checking overloading of `%s' in package `%.256s'\n",
1361 cp, HvNAME(stash)) );
1362 /* don't fill the cache while looking up!
1363 Creation of inheritance stubs in intermediate packages may
1364 conflict with the logic of runtime method substitution.
1365 Indeed, for inheritance A -> B -> C, if C overloads "+0",
1366 then we could have created stubs for "(+0" in A and C too.
1367 But if B overloads "bool", we may want to use it for
1368 numifying instead of C's "+0". */
1369 if (i >= DESTROY_amg)
1370 gv = Perl_gv_fetchmeth_autoload(aTHX_ stash, cooky, l, 0);
1371 else /* Autoload taken care of below */
1372 gv = Perl_gv_fetchmeth(aTHX_ stash, cooky, l, -1);
1374 if (gv && (cv = GvCV(gv))) {
1375 if (GvNAMELEN(CvGV(cv)) == 3 && strEQ(GvNAME(CvGV(cv)), "nil")
1376 && strEQ(HvNAME(GvSTASH(CvGV(cv))), "overload")) {
1377 /* This is a hack to support autoloading..., while
1378 knowing *which* methods were declared as overloaded. */
1379 /* GvSV contains the name of the method. */
1382 DEBUG_o( Perl_deb(aTHX_ "Resolving method `%"SVf256\
1383 "' for overloaded `%s' in package `%.256s'\n",
1384 GvSV(gv), cp, HvNAME(stash)) );
1385 if (!SvPOK(GvSV(gv))
1386 || !(ngv = gv_fetchmethod_autoload(stash, SvPVX(GvSV(gv)),
1389 /* Can be an import stub (created by `can'). */
1390 SV *gvsv = GvSV(gv);
1391 const char *name = SvPOK(gvsv) ? SvPVX(gvsv) : "???";
1392 Perl_croak(aTHX_ "%s method `%.256s' overloading `%s' "\
1393 "in package `%.256s'",
1394 (GvCVGEN(gv) ? "Stub found while resolving"
1396 name, cp, HvNAME(stash));
1398 cv = GvCV(gv = ngv);
1400 DEBUG_o( Perl_deb(aTHX_ "Overloading `%s' in package `%.256s' via `%.256s::%.256s' \n",
1401 cp, HvNAME(stash), HvNAME(GvSTASH(CvGV(cv))),
1402 GvNAME(CvGV(cv))) );
1404 if (i < DESTROY_amg)
1406 } else if (gv) { /* Autoloaded... */
1410 amt.table[i]=(CV*)SvREFCNT_inc(cv);
1413 AMT_AMAGIC_on(&amt);
1415 AMT_OVERLOADED_on(&amt);
1416 sv_magic((SV*)stash, 0, PERL_MAGIC_overload_table,
1417 (char*)&amt, sizeof(AMT));
1421 /* Here we have no table: */
1423 AMT_AMAGIC_off(&amt);
1424 sv_magic((SV*)stash, 0, PERL_MAGIC_overload_table,
1425 (char*)&amt, sizeof(AMTS));
1431 Perl_gv_handler(pTHX_ HV *stash, I32 id)
1437 if (!stash || !HvNAME(stash))
1439 mg = mg_find((SV*)stash, PERL_MAGIC_overload_table);
1443 mg = mg_find((SV*)stash, PERL_MAGIC_overload_table);
1445 amtp = (AMT*)mg->mg_ptr;
1446 if ( amtp->was_ok_am != PL_amagic_generation
1447 || amtp->was_ok_sub != PL_sub_generation )
1449 if (AMT_AMAGIC(amtp)) {
1450 ret = amtp->table[id];
1451 if (ret && isGV(ret)) { /* Autoloading stab */
1452 /* Passing it through may have resulted in a warning
1453 "Inherited AUTOLOAD for a non-method deprecated", since
1454 our caller is going through a function call, not a method call.
1455 So return the CV for AUTOLOAD, setting $AUTOLOAD. */
1456 GV *gv = gv_fetchmethod(stash, (char*)PL_AMG_names[id]);
1469 Perl_amagic_call(pTHX_ SV *left, SV *right, int method, int flags)
1473 CV **cvp=NULL, **ocvp=NULL;
1474 AMT *amtp=NULL, *oamtp=NULL;
1475 int off=0, off1, lr=0, assign=AMGf_assign & flags, notfound=0;
1476 int postpr = 0, force_cpy = 0, assignshift = assign ? 1 : 0;
1481 if (!(AMGf_noleft & flags) && SvAMAGIC(left)
1482 && (stash = SvSTASH(SvRV(left)))
1483 && (mg = mg_find((SV*)stash, PERL_MAGIC_overload_table))
1484 && (ocvp = cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
1485 ? (oamtp = amtp = (AMT*)mg->mg_ptr)->table
1487 && ((cv = cvp[off=method+assignshift])
1488 || (assign && amtp->fallback > AMGfallNEVER && /* fallback to
1494 cv = cvp[off=method])))) {
1495 lr = -1; /* Call method for left argument */
1497 if (cvp && amtp->fallback > AMGfallNEVER && flags & AMGf_unary) {
1500 /* look for substituted methods */
1501 /* In all the covered cases we should be called with assign==0. */
1505 if ((cv = cvp[off=add_ass_amg])
1506 || ((cv = cvp[off = add_amg]) && (force_cpy = 0, postpr = 1))) {
1507 right = &PL_sv_yes; lr = -1; assign = 1;
1512 if ((cv = cvp[off = subtr_ass_amg])
1513 || ((cv = cvp[off = subtr_amg]) && (force_cpy = 0, postpr=1))) {
1514 right = &PL_sv_yes; lr = -1; assign = 1;
1518 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=string_amg]));
1521 (void)((cv = cvp[off=string_amg]) || (cv = cvp[off=bool__amg]));
1524 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=bool__amg]));
1527 (void)((cv = cvp[off=bool__amg])
1528 || (cv = cvp[off=numer_amg])
1529 || (cv = cvp[off=string_amg]));
1535 * SV* ref causes confusion with the interpreter variable of
1538 SV* tmpRef=SvRV(left);
1539 if (!SvROK(tmpRef) && SvTYPE(tmpRef) <= SVt_PVMG) {
1541 * Just to be extra cautious. Maybe in some
1542 * additional cases sv_setsv is safe, too.
1544 SV* newref = newSVsv(tmpRef);
1545 SvOBJECT_on(newref);
1546 SvSTASH(newref) = (HV*)SvREFCNT_inc(SvSTASH(tmpRef));
1552 if ((cvp[off1=lt_amg] || cvp[off1=ncmp_amg])
1553 && ((cv = cvp[off=neg_amg]) || (cv = cvp[off=subtr_amg]))) {
1554 SV* nullsv=sv_2mortal(newSViv(0));
1556 SV* lessp = amagic_call(left,nullsv,
1557 lt_amg,AMGf_noright);
1558 logic = SvTRUE(lessp);
1560 SV* lessp = amagic_call(left,nullsv,
1561 ncmp_amg,AMGf_noright);
1562 logic = (SvNV(lessp) < 0);
1565 if (off==subtr_amg) {
1576 if ((cv = cvp[off=subtr_amg])) {
1578 left = sv_2mortal(newSViv(0));
1583 case iter_amg: /* XXXX Eventually should do to_gv. */
1585 return NULL; /* Delegate operation to standard mechanisms. */
1593 return left; /* Delegate operation to standard mechanisms. */
1598 if (!cv) goto not_found;
1599 } else if (!(AMGf_noright & flags) && SvAMAGIC(right)
1600 && (stash = SvSTASH(SvRV(right)))
1601 && (mg = mg_find((SV*)stash, PERL_MAGIC_overload_table))
1602 && (cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
1603 ? (amtp = (AMT*)mg->mg_ptr)->table
1605 && (cv = cvp[off=method])) { /* Method for right
1608 } else if (((ocvp && oamtp->fallback > AMGfallNEVER
1609 && (cvp=ocvp) && (lr = -1))
1610 || (cvp && amtp->fallback > AMGfallNEVER && (lr=1)))
1611 && !(flags & AMGf_unary)) {
1612 /* We look for substitution for
1613 * comparison operations and
1615 if (method==concat_amg || method==concat_ass_amg
1616 || method==repeat_amg || method==repeat_ass_amg) {
1617 return NULL; /* Delegate operation to string conversion */
1627 postpr = 1; off=ncmp_amg; break;
1634 postpr = 1; off=scmp_amg; break;
1636 if (off != -1) cv = cvp[off];
1641 not_found: /* No method found, either report or croak */
1649 return left; /* Delegate operation to standard mechanisms. */
1652 if (ocvp && (cv=ocvp[nomethod_amg])) { /* Call report method */
1653 notfound = 1; lr = -1;
1654 } else if (cvp && (cv=cvp[nomethod_amg])) {
1655 notfound = 1; lr = 1;
1658 if (off==-1) off=method;
1659 msg = sv_2mortal(Perl_newSVpvf(aTHX_
1660 "Operation `%s': no method found,%sargument %s%s%s%s",
1661 AMG_id2name(method + assignshift),
1662 (flags & AMGf_unary ? " " : "\n\tleft "),
1664 "in overloaded package ":
1665 "has no overloaded magic",
1667 HvNAME(SvSTASH(SvRV(left))):
1670 ",\n\tright argument in overloaded package ":
1673 : ",\n\tright argument has no overloaded magic"),
1675 HvNAME(SvSTASH(SvRV(right))):
1677 if (amtp && amtp->fallback >= AMGfallYES) {
1678 DEBUG_o( Perl_deb(aTHX_ "%s", SvPVX(msg)) );
1680 Perl_croak(aTHX_ "%"SVf, msg);
1684 force_cpy = force_cpy || assign;
1689 DEBUG_o(Perl_deb(aTHX_
1690 "Overloaded operator `%s'%s%s%s:\n\tmethod%s found%s in package %s%s\n",
1692 method+assignshift==off? "" :
1694 method+assignshift==off? "" :
1695 AMG_id2name(method+assignshift),
1696 method+assignshift==off? "" : "')",
1697 flags & AMGf_unary? "" :
1698 lr==1 ? " for right argument": " for left argument",
1699 flags & AMGf_unary? " for argument" : "",
1700 stash ? HvNAME(stash) : "null",
1701 fl? ",\n\tassignment variant used": "") );
1704 /* Since we use shallow copy during assignment, we need
1705 * to dublicate the contents, probably calling user-supplied
1706 * version of copy operator
1708 /* We need to copy in following cases:
1709 * a) Assignment form was called.
1710 * assignshift==1, assign==T, method + 1 == off
1711 * b) Increment or decrement, called directly.
1712 * assignshift==0, assign==0, method + 0 == off
1713 * c) Increment or decrement, translated to assignment add/subtr.
1714 * assignshift==0, assign==T,
1716 * d) Increment or decrement, translated to nomethod.
1717 * assignshift==0, assign==0,
1719 * e) Assignment form translated to nomethod.
1720 * assignshift==1, assign==T, method + 1 != off
1723 /* off is method, method+assignshift, or a result of opcode substitution.
1724 * In the latter case assignshift==0, so only notfound case is important.
1726 if (( (method + assignshift == off)
1727 && (assign || (method == inc_amg) || (method == dec_amg)))
1734 bool oldcatch = CATCH_GET;
1737 Zero(&myop, 1, BINOP);
1738 myop.op_last = (OP *) &myop;
1739 myop.op_next = Nullop;
1740 myop.op_flags = OPf_WANT_SCALAR | OPf_STACKED;
1742 PUSHSTACKi(PERLSI_OVERLOAD);
1745 PL_op = (OP *) &myop;
1746 if (PERLDB_SUB && PL_curstash != PL_debstash)
1747 PL_op->op_private |= OPpENTERSUB_DB;
1751 EXTEND(SP, notfound + 5);
1752 PUSHs(lr>0? right: left);
1753 PUSHs(lr>0? left: right);
1754 PUSHs( lr > 0 ? &PL_sv_yes : ( assign ? &PL_sv_undef : &PL_sv_no ));
1756 PUSHs( sv_2mortal(newSVpv(AMG_id2name(method + assignshift),0)));
1761 if ((PL_op = Perl_pp_entersub(aTHX)))
1769 CATCH_SET(oldcatch);
1776 ans=SvIV(res)<=0; break;
1779 ans=SvIV(res)<0; break;
1782 ans=SvIV(res)>=0; break;
1785 ans=SvIV(res)>0; break;
1788 ans=SvIV(res)==0; break;
1791 ans=SvIV(res)!=0; break;
1794 SvSetSV(left,res); return left;
1796 ans=!SvTRUE(res); break;
1799 } else if (method==copy_amg) {
1801 Perl_croak(aTHX_ "Copy method did not return a reference");
1803 return SvREFCNT_inc(SvRV(res));
1811 =for apidoc is_gv_magical
1813 Returns C<TRUE> if given the name of a magical GV.
1815 Currently only useful internally when determining if a GV should be
1816 created even in rvalue contexts.
1818 C<flags> is not used at present but available for future extension to
1819 allow selecting particular classes of magical variable.
1824 Perl_is_gv_magical(pTHX_ char *name, STRLEN len, U32 flags)
1831 if (len == 3 && strEQ(name, "ISA"))
1835 if (len == 8 && strEQ(name, "OVERLOAD"))
1839 if (len == 3 && strEQ(name, "SIG"))
1842 case '\017': /* $^O & $^OPEN */
1844 || (len == 4 && strEQ(name, "\017PEN")))
1850 if (len > 1 && strEQ(name, "\025NICODE"))
1852 case '\027': /* $^W & $^WARNING_BITS */
1854 || (len == 12 && strEQ(name, "\027ARNING_BITS"))
1886 case '\001': /* $^A */
1887 case '\003': /* $^C */
1888 case '\004': /* $^D */
1889 case '\005': /* $^E */
1890 case '\006': /* $^F */
1891 case '\010': /* $^H */
1892 case '\011': /* $^I, NOT \t in EBCDIC */
1893 case '\014': /* $^L */
1894 case '\016': /* $^N */
1895 case '\020': /* $^P */
1896 case '\023': /* $^S */
1897 case '\026': /* $^V */
1901 case '\024': /* $^T, ${^TAINT} */
1902 if (len == 1 || strEQ(name, "\024AINT"))
1915 char *end = name + len;
1916 while (--end > name) {