PERLAPI

perlapi − autogenerated documentation for the perl public API

This file contains the documentation of the perl public API generated by embed.pl, specifically a listing of functions, macros, flags, and variables that may be used by extension writers. The interfaces of any functions that are not listed here are subject to change without notice. For this reason, blindly using functions listed in proto.h is to be avoided when writing extensions.

Note that all Perl API global variables must be referenced with the "PL_" prefix. Some macros are provided for compatibility with the older, unadorned names, but this support may be disabled in a future release.

Perl was originally written to handle US-ASCII only (that is characters whose ordinal numbers are in the range 0 − 127). And documentation and comments may still use the term ASCII , when sometimes in fact the entire range from 0 − 255 is meant.

Note that Perl can be compiled and run under EBCDIC (See perlebcdic) or ASCII . Most of the documentation (and even comments in the code) ignore the EBCDIC possibility. For almost all purposes the differences are transparent. As an example, under EBCDIC , instead of UTF−8 , UTF-EBCDIC is used to encode Unicode strings, and so whenever this documentation refers to "utf8" (and variants of that name, including in function names), it also (essentially transparently) means "UTF−EBCDIC". But the ordinals of characters differ between ASCII , EBCDIC , and the UTF− encodings, and a string encoded in UTF-EBCDIC may occupy more bytes than in UTF−8 .

Also, on some EBCDIC machines, functions that are documented as operating on US-ASCII (or Basic Latin in Unicode terminology) may in fact operate on all 256 characters in the EBCDIC range, not just the subset corresponding to US-ASCII.

The listing below is alphabetical, case insensitive.

GIMME

A backward-compatible version of "GIMME_V" which can only return "G_SCALAR" or "G_ARRAY"; in a void context, it returns "G_SCALAR". Deprecated. Use "GIMME_V" instead.

        U32     GIMME

GIMME_V

The XSUB-writer’s equivalent to Perl’s "wantarray". Returns "G_VOID", "G_SCALAR" or "G_ARRAY" for void, scalar or list context, respectively.

        U32     GIMME_V

G_ARRAY

Used to indicate list context. See "GIMME_V", "GIMME" and perlcall.

G_DISCARD

Indicates that arguments returned from a callback should be discarded. See perlcall.

G_EVAL

Used to force a Perl "eval" wrapper around a callback. See perlcall.

G_NOARGS

Indicates that no arguments are being sent to a callback. See perlcall.

G_SCALAR

Used to indicate scalar context. See "GIMME_V", "GIMME", and perlcall.

G_VOID

Used to indicate void context. See "GIMME_V" and perlcall.

AvFILL

Same as "av_len()". Deprecated, use "av_len()" instead.

        int     AvFILL(AV* av)

av_clear

Clears an array, making it empty. Does not free the memory used by the array itself.

        void    av_clear(AV *av)

av_create_and_push

Push an SV onto the end of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.

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

        void    av_create_and_push(AV **const avp, SV *const val)

av_create_and_unshift_one

Unshifts an SV onto the beginning of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.

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

        SV**    av_create_and_unshift_one(AV **const avp, SV *const val)

av_delete

Deletes the element indexed by "key" from the array. Returns the deleted element. If "flags" equals "G_DISCARD", the element is freed and null is returned.

        SV*     av_delete(AV *av, I32 key, I32 flags)

av_exists

Returns true if the element indexed by "key" has been initialized.

This relies on the fact that uninitialized array elements are set to &PL_sv_undef.

        bool    av_exists(AV *av, I32 key)

av_extend

Pre-extend an array. The "key" is the index to which the array should be extended.

        void    av_extend(AV *av, I32 key)

av_fetch

Returns the SV at the specified index in the array. The "key" is the index. If "lval" is set then the fetch will be part of a store. Check that the return value is non-null before dereferencing it to a "SV*".

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.

        SV**    av_fetch(AV *av, I32 key, I32 lval)

av_fill

Set the highest index in the array to the given number, equivalent to Perl’s "$#array = $fill;".

The number of elements in the an array will be "fill + 1" after av_fill() returns. If the array was previously shorter then the additional elements appended are set to "PL_sv_undef". If the array was longer, then the excess elements are freed. "av_fill(av, −1)" is the same as "av_clear(av)".

        void    av_fill(AV *av, I32 fill)

av_len

Returns the highest index in the array. The number of elements in the array is "av_len(av) + 1". Returns −1 if the array is empty.

        I32     av_len(const AV *av)

av_make

Creates a new AV and populates it with a list of SVs. The SVs are copied into the array, so they may be freed after the call to av_make. The new AV will have a reference count of 1.

        AV*     av_make(I32 size, SV **strp)

av_pop

Pops an SV off the end of the array. Returns &PL_sv_undef if the array is empty.

        SV*     av_pop(AV *av)

av_push

Pushes an SV onto the end of the array. The array will grow automatically to accommodate the addition. Like "av_store", this takes ownership of one reference count.

        void    av_push(AV *av, SV *val)

av_shift

Shifts an SV off the beginning of the array. Returns &PL_sv_undef if the array is empty.

        SV*     av_shift(AV *av)

av_store

Stores an SV in an array. The array index is specified as "key". The return value will be NULL if the operation failed or if the value did not need to be actually stored within the array (as in the case of tied arrays). Otherwise it can be dereferenced to get the original "SV*". Note that the caller is responsible for suitably incrementing the reference count of "val" before the call, and decrementing it if the function returned NULL .

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.

        SV**    av_store(AV *av, I32 key, SV *val)

av_undef

Undefines the array. Frees the memory used by the array itself.

        void    av_undef(AV *av)

av_unshift

Unshift the given number of "undef" values onto the beginning of the array. The array will grow automatically to accommodate the addition. You must then use "av_store" to assign values to these new elements.

        void    av_unshift(AV *av, I32 num)

get_av

Returns the AV of the specified Perl array. "flags" are passed to "gv_fetchpv". If "GV_ADD" is set and the Perl variable does not exist then it will be created. If "flags" is zero and the variable does not exist then NULL is returned.

NOTE: the perl_ form of this function is deprecated.

        AV*     get_av(const char *name, I32 flags)

newAV

Creates a new AV . The reference count is set to 1.

        AV*     newAV()

sortsv

Sort an array. Here is an example:

    sortsv(AvARRAY(av), av_len(av)+1, Perl_sv_cmp_locale);

Currently this always uses mergesort. See sortsv_flags for a more flexible routine.

        void    sortsv(SV** array, size_t num_elts, SVCOMPARE_t cmp)

sortsv_flags

Sort an array, with various options.

        void    sortsv_flags(SV** array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)

call_argv

Performs a callback to the specified Perl sub. See perlcall.

NOTE: the perl_ form of this function is deprecated.

        I32     call_argv(const char* sub_name, I32 flags, char** argv)

call_method

Performs a callback to the specified Perl method. The blessed object must be on the stack. See perlcall.

NOTE: the perl_ form of this function is deprecated.

        I32     call_method(const char* methname, I32 flags)

call_pv

Performs a callback to the specified Perl sub. See perlcall.

NOTE: the perl_ form of this function is deprecated.

        I32     call_pv(const char* sub_name, I32 flags)

call_sv

Performs a callback to the Perl sub whose name is in the SV . See perlcall.

NOTE: the perl_ form of this function is deprecated.

        I32     call_sv(SV* sv, VOL I32 flags)

ENTER

Opening bracket on a callback. See "LEAVE" and perlcall.

                ENTER;

eval_pv

Tells Perl to "eval" the given string and return an SV* result.

NOTE: the perl_ form of this function is deprecated.

        SV*     eval_pv(const char* p, I32 croak_on_error)

eval_sv

Tells Perl to "eval" the string in the SV .

NOTE: the perl_ form of this function is deprecated.

        I32     eval_sv(SV* sv, I32 flags)

FREETMPS

Closing bracket for temporaries on a callback. See "SAVETMPS" and perlcall.

                FREETMPS;

LEAVE

Closing bracket on a callback. See "ENTER" and perlcall.

                LEAVE;

SAVETMPS

Opening bracket for temporaries on a callback. See "FREETMPS" and perlcall.

                SAVETMPS;

isALNUM

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) alphanumeric character (including underscore) or digit.

        bool    isALNUM(char ch)

isALPHA

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) alphabetic character.

        bool    isALPHA(char ch)

isDIGIT

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) digit.

        bool    isDIGIT(char ch)

isLOWER

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) lowercase character.

        bool    isLOWER(char ch)

isSPACE

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) whitespace.

        bool    isSPACE(char ch)

isUPPER

Returns a boolean indicating whether the C "char" is a US-ASCII (Basic Latin) uppercase character.

        bool    isUPPER(char ch)

toLOWER

Converts the specified character to lowercase. Characters outside the US-ASCII (Basic Latin) range are viewed as not having any case.

        char    toLOWER(char ch)

toUPPER

Converts the specified character to uppercase. Characters outside the US-ASCII (Basic Latin) range are viewed as not having any case.

        char    toUPPER(char ch)

perl_clone

Create and return a new interpreter by cloning the current one.

perl_clone takes these flags as parameters:

CLONEf_COPY_STACKS − is used to, well, copy the stacks also, without it we only clone the data and zero the stacks, with it we copy the stacks and the new perl interpreter is ready to run at the exact same point as the previous one. The pseudo-fork code uses COPY_STACKS while the threads−>create doesn’t.

CLONEf_KEEP_PTR_TABLE perl_clone keeps a ptr_table with the pointer of the old variable as a key and the new variable as a value, this allows it to check if something has been cloned and not clone it again but rather just use the value and increase the refcount. If KEEP_PTR_TABLE is not set then perl_clone will kill the ptr_table using the function "ptr_table_free(PL_ptr_table); PL_ptr_table = NULL;", reason to keep it around is if you want to dup some of your own variable who are outside the graph perl scans, example of this code is in threads.xs create

CLONEf_CLONE_HOST This is a win32 thing, it is ignored on unix, it tells perls win32host code (which is c++) to clone itself, this is needed on win32 if you want to run two threads at the same time, if you just want to do some stuff in a separate perl interpreter and then throw it away and return to the original one, you don’t need to do anything.

        PerlInterpreter*        perl_clone(PerlInterpreter *proto_perl, UV flags)

CvSTASH

Returns the stash of the CV .

        HV*     CvSTASH(CV* cv)

get_cv

Uses "strlen" to get the length of "name", then calls "get_cvn_flags".

NOTE: the perl_ form of this function is deprecated.

        CV*     get_cv(const char* name, I32 flags)

get_cvn_flags

Returns the CV of the specified Perl subroutine. "flags" are passed to "gv_fetchpvn_flags". If "GV_ADD" is set and the Perl subroutine does not exist then it will be declared (which has the same effect as saying "sub name;"). If "GV_ADD" is not set and the subroutine does not exist then NULL is returned.

NOTE: the perl_ form of this function is deprecated.

        CV*     get_cvn_flags(const char* name, STRLEN len, I32 flags)

cv_undef

Clear out all the active components of a CV . This can happen either by an explicit "undef &foo", or by the reference count going to zero. In the former case, we keep the CvOUTSIDE pointer, so that any anonymous children can still follow the full lexical scope chain.

        void    cv_undef(CV* cv)

load_module

Loads the module whose name is pointed to by the string part of name. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". flags can be any of PERL_LOADMOD_DENY , PERL_LOADMOD_NOIMPORT , or PERL_LOADMOD_IMPORT_OPS (or 0 for no flags). ver, if specified, provides version semantics similar to "use Foo::Bar VERSION". The optional trailing SV* arguments can be used to specify arguments to the module’s import() method, similar to "use Foo::Bar VERSION LIST". They must be terminated with a final NULL pointer. Note that this list can only be omitted when the PERL_LOADMOD_NOIMPORT flag has been used. Otherwise at least a single NULL pointer to designate the default import list is required.

        void    load_module(U32 flags, SV* name, SV* ver, ...)

nothreadhook

Stub that provides thread hook for perl_destruct when there are no threads.

        int     nothreadhook()

perl_alloc

Allocates a new Perl interpreter. See perlembed.

        PerlInterpreter*        perl_alloc()

perl_construct

Initializes a new Perl interpreter. See perlembed.

        void    perl_construct(PerlInterpreter *my_perl)

perl_destruct

Shuts down a Perl interpreter. See perlembed.

        int     perl_destruct(PerlInterpreter *my_perl)

perl_free

Releases a Perl interpreter. See perlembed.

        void    perl_free(PerlInterpreter *my_perl)

perl_parse

Tells a Perl interpreter to parse a Perl script. See perlembed.

        int     perl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char** argv, char** env)

perl_run

Tells a Perl interpreter to run. See perlembed.

        int     perl_run(PerlInterpreter *my_perl)

require_pv

Tells Perl to "require" the file named by the string argument. It is analogous to the Perl code "eval "require '$file'"". It’s even implemented that way; consider using load_module instead.

NOTE: the perl_ form of this function is deprecated.

        void    require_pv(const char* pv)

pv_display

Similar to

  pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);

except that an additional "\0" will be appended to the string when len > cur and pv[cur] is "\0".

Note that the final string may be up to 7 chars longer than pvlim.

        char*   pv_display(SV *dsv, const char *pv, STRLEN cur, STRLEN len, STRLEN pvlim)

pv_escape

Escapes at most the first "count" chars of pv and puts the results into dsv such that the size of the escaped string will not exceed "max" chars and will not contain any incomplete escape sequences.

If flags contains PERL_PV_ESCAPE_QUOTE then any double quotes in the string will also be escaped.

Normally the SV will be cleared before the escaped string is prepared, but when PERL_PV_ESCAPE_NOCLEAR is set this will not occur.

If PERL_PV_ESCAPE_UNI is set then the input string is treated as Unicode, if PERL_PV_ESCAPE_UNI_DETECT is set then the input string is scanned using "is_utf8_string()" to determine if it is Unicode.

If PERL_PV_ESCAPE_ALL is set then all input chars will be output using "\x01F1" style escapes, otherwise only chars above 255 will be escaped using this style, other non printable chars will use octal or common escaped patterns like "\n". If PERL_PV_ESCAPE_NOBACKSLASH then all chars below 255 will be treated as printable and will be output as literals.

If PERL_PV_ESCAPE_FIRSTCHAR is set then only the first char of the string will be escaped, regardles of max. If the string is utf8 and the chars value is >255 then it will be returned as a plain hex sequence. Thus the output will either be a single char, an octal escape sequence, a special escape like "\n" or a 3 or more digit hex value.

If PERL_PV_ESCAPE_RE is set then the escape char used will be a ’%’ and not a ’\\’. This is because regexes very often contain backslashed sequences, whereas ’%’ is not a particularly common character in patterns.

Returns a pointer to the escaped text as held by dsv.

        char*   pv_escape(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, STRLEN * const escaped, const U32 flags)

pv_pretty

Converts a string into something presentable, handling escaping via pv_escape() and supporting quoting and ellipses.

If the PERL_PV_PRETTY_QUOTE flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if the PERL_PV_PRETTY_LTGT flag is set then the result be wrapped in angle brackets.

If the PERL_PV_PRETTY_ELLIPSES flag is set and not all characters in string were output then an ellipsis "..." will be appended to the string. Note that this happens AFTER it has been quoted.

If start_color is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. If end_color is non-null then it will be inserted after the escaped text but before any quotes or ellipses.

Returns a pointer to the prettified text as held by dsv.

        char*   pv_pretty(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, char const * const start_color, char const * const end_color, const U32 flags)

gv_fetchmethod

See gv_fetchmethod_autoload.

        GV*     gv_fetchmethod(HV* stash, const char* name)

pack_cat

The engine implementing pack() Perl function. Note: parameters next_in_list and flags are not used. This call should not be used; use packlist instead.

        void    pack_cat(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags)

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)

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)

sv_2pv_nolen

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

sv_catpvn_mg

Like "sv_catpvn", but also handles ’set’ magic.

        void    sv_catpvn_mg(SV *sv, const char *ptr, STRLEN len)

sv_catsv_mg

Like "sv_catsv", but also handles ’set’ magic.

        void    sv_catsv_mg(SV *dsv, SV *ssv)

sv_force_normal

Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we’re a ref, stop refing; if we’re a glob, downgrade to an xpvmg. See also "sv_force_normal_flags".

        void    sv_force_normal(SV *sv)

sv_iv

A private implementation of the "SvIVx" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        IV      sv_iv(SV* sv)

sv_nolocking

Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.

"Superseded" by sv_nosharing().

        void    sv_nolocking(SV *sv)

sv_nounlocking

Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.

"Superseded" by sv_nosharing().

        void    sv_nounlocking(SV *sv)

sv_nv

A private implementation of the "SvNVx" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        NV      sv_nv(SV* sv)

sv_pv

Use the "SvPV_nolen" macro instead

        char*   sv_pv(SV *sv)

sv_pvbyte

Use "SvPVbyte_nolen" instead.

        char*   sv_pvbyte(SV *sv)

sv_pvbyten

A private implementation of the "SvPVbyte" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        char*   sv_pvbyten(SV *sv, STRLEN *lp)

sv_pvn

A private implementation of the "SvPV" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        char*   sv_pvn(SV *sv, STRLEN *lp)

sv_pvutf8

Use the "SvPVutf8_nolen" macro instead

        char*   sv_pvutf8(SV *sv)

sv_pvutf8n

A private implementation of the "SvPVutf8" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        char*   sv_pvutf8n(SV *sv, STRLEN *lp)

sv_taint

Taint an SV . Use "SvTAINTED_on" instead.

sv_unref

Unsets the RV status of the SV , and decrements the reference count of whatever was being referenced by the RV . This can almost be thought of as a reversal of "newSVrv". This is "sv_unref_flags" with the "flag" being zero. See "SvROK_off".

        void    sv_unref(SV* sv)

sv_usepvn

Tells an SV to use "ptr" to find its string value. Implemented by calling "sv_usepvn_flags" with "flags" of 0, hence does not handle ’set’ magic. See "sv_usepvn_flags".

        void    sv_usepvn(SV* sv, char* ptr, STRLEN len)

sv_usepvn_mg

Like "sv_usepvn", but also handles ’set’ magic.

        void    sv_usepvn_mg(SV *sv, char *ptr, STRLEN len)

sv_uv

A private implementation of the "SvUVx" macro for compilers which can’t cope with complex macro expressions. Always use the macro instead.

        UV      sv_uv(SV* sv)

unpack_str

The engine implementing unpack() Perl function. Note: parameters strbeg, new_s and ocnt are not used. This call should not be used, use unpackstring instead.

        I32     unpack_str(const char *pat, const char *patend, const char *s, const char *strbeg, const char *strend, char **new_s, I32 ocnt, U32 flags)

PERL_SYS_INIT

Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.

        void    PERL_SYS_INIT(int argc, char** argv)

PERL_SYS_INIT3

Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.

        void    PERL_SYS_INIT3(int argc, char** argv, char** env)

PERL_SYS_TERM

Provides system-specific clean up of the C runtime environment after running Perl interpreters. This should be called only once, after freeing any remaining Perl interpreters.

        void    PERL_SYS_TERM()

find_runcv

Locate the CV corresponding to the currently executing sub or eval. If db_seqp is non_null, skip CVs that are in the DB package and populate *db_seqp with the cop sequence number at the point that the DB:: code was entered. (allows debuggers to eval in the scope of the breakpoint rather than in the scope of the debugger itself).

        CV*     find_runcv(U32 *db_seqp)

packlist

The engine implementing pack() Perl function.

        void    packlist(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist)

unpackstring

The engine implementing unpack() Perl function. "unpackstring" puts the extracted list items on the stack and returns the number of elements. Issue "PUTBACK" before and "SPAGAIN" after the call to this function.

        I32     unpackstring(const char *pat, const char *patend, const char *s, const char *strend, U32 flags)

GvSV

Return the SV from the GV .

        SV*     GvSV(GV* gv)

gv_const_sv

If "gv" is a typeglob whose subroutine entry is a constant sub eligible for inlining, or "gv" is a placeholder reference that would be promoted to such a typeglob, then returns the value returned by the sub. Otherwise, returns NULL .

        SV*     gv_const_sv(GV* gv)

gv_fetchmeth

Returns the glob with the given "name" and a defined subroutine or "NULL". The glob lives in the given "stash", or in the stashes accessible via @ISA and UNIVERSAL:: .

The argument "level" should be either 0 or −1. If "level==0", as a side-effect creates a glob with the given "name" in the given "stash" which in the case of success contains an alias for the subroutine, and sets up caching info for this glob.

This function grants "SUPER" token as a postfix of the stash name. The GV returned from "gv_fetchmeth" may be a method cache entry, which is not visible to Perl code. So when calling "call_sv", you should not use the GV directly; instead, you should use the method’s CV , which can be obtained from the GV with the "GvCV" macro.

        GV*     gv_fetchmeth(HV* stash, const char* name, STRLEN len, I32 level)

gv_fetchmethod_autoload

Returns the glob which contains the subroutine to call to invoke the method on the "stash". In fact in the presence of autoloading this may be the glob for " AUTOLOAD ". In this case the corresponding variable $AUTOLOAD is already setup.

The third parameter of "gv_fetchmethod_autoload" determines whether AUTOLOAD lookup is performed if the given method is not present: non-zero means yes, look for AUTOLOAD ; zero means no, don’t look for AUTOLOAD . Calling "gv_fetchmethod" is equivalent to calling "gv_fetchmethod_autoload" with a non-zero "autoload" parameter.

These functions grant "SUPER" token as a prefix of the method name. Note that if you want to keep the returned glob for a long time, you need to check for it being " AUTOLOAD ", since at the later time the call may load a different subroutine due to $AUTOLOAD changing its value. Use the glob created via a side effect to do this.

These functions have the same side-effects and as "gv_fetchmeth" with "level==0". "name" should be writable if contains ':' or ' ''. The warning against passing the GV returned by "gv_fetchmeth" to "call_sv" apply equally to these functions.

        GV*     gv_fetchmethod_autoload(HV* stash, const char* name, I32 autoload)

gv_fetchmeth_autoload

Same as gv_fetchmeth(), but looks for autoloaded subroutines too. Returns a glob for the subroutine.

For an autoloaded subroutine without a GV , will create a GV even if "level < 0". For an autoloaded subroutine without a stub, GvCV() of the result may be zero.

        GV*     gv_fetchmeth_autoload(HV* stash, const char* name, STRLEN len, I32 level)

gv_stashpv

Returns a pointer to the stash for a specified package. Uses "strlen" to determine the length of "name", then calls "gv_stashpvn()".

        HV*     gv_stashpv(const char* name, I32 flags)

gv_stashpvn

Returns a pointer to the stash for a specified package. The "namelen" parameter indicates the length of the "name", in bytes. "flags" is passed to "gv_fetchpvn_flags()", so if set to "GV_ADD" then the package will be created if it does not already exist. If the package does not exist and "flags" is 0 (or any other setting that does not create packages) then NULL is returned.

        HV*     gv_stashpvn(const char* name, U32 namelen, I32 flags)

gv_stashpvs

Like "gv_stashpvn", but takes a literal string instead of a string/length pair.

        HV*     gv_stashpvs(const char* name, I32 create)

gv_stashsv

Returns a pointer to the stash for a specified package. See "gv_stashpvn".

        HV*     gv_stashsv(SV* sv, I32 flags)

Nullav

Null AV pointer.

Nullch

Null character pointer.

Nullcv

Null CV pointer.

Nullhv

Null HV pointer.

Nullsv

Null SV pointer.

get_hv

Returns the HV of the specified Perl hash. "flags" are passed to "gv_fetchpv". If "GV_ADD" is set and the Perl variable does not exist then it will be created. If "flags" is zero and the variable does not exist then NULL is returned.

NOTE: the perl_ form of this function is deprecated.

        HV*     get_hv(const char *name, I32 flags)

HEf_SVKEY

This flag, used in the length slot of hash entries and magic structures, specifies the structure contains an "SV*" pointer where a "char*" pointer is to be expected. (For information only--not to be used).

HeHASH

Returns the computed hash stored in the hash entry.

        U32     HeHASH(HE* he)

HeKEY

Returns the actual pointer stored in the key slot of the hash entry. The pointer may be either "char*" or "SV*", depending on the value of "HeKLEN()". Can be assigned to. The "HePV()" or "HeSVKEY()" macros are usually preferable for finding the value of a key.

        void*   HeKEY(HE* he)

HeKLEN

If this is negative, and amounts to "HEf_SVKEY", it indicates the entry holds an "SV*" key. Otherwise, holds the actual length of the key. Can be assigned to. The "HePV()" macro is usually preferable for finding key lengths.

        STRLEN  HeKLEN(HE* he)

HePV

Returns the key slot of the hash entry as a "char*" value, doing any necessary dereferencing of possibly "SV*" keys. The length of the string is placed in "len" (this is a macro, so do not use &len). If you do not care about what the length of the key is, you may use the global variable "PL_na", though this is rather less efficient than using a local variable. Remember though, that hash keys in perl are free to contain embedded nulls, so using "strlen()" or similar is not a good way to find the length of hash keys. This is very similar to the "SvPV()" macro described elsewhere in this document. See also "HeUTF8".

If you are using "HePV" to get values to pass to "newSVpvn()" to create a new SV , you should consider using "newSVhek(HeKEY_hek(he))" as it is more efficient.

        char*   HePV(HE* he, STRLEN len)

HeSVKEY

Returns the key as an "SV*", or "NULL" if the hash entry does not contain an "SV*" key.

        SV*     HeSVKEY(HE* he)

HeSVKEY_force

Returns the key as an "SV*". Will create and return a temporary mortal "SV*" if the hash entry contains only a "char*" key.

        SV*     HeSVKEY_force(HE* he)

HeSVKEY_set

Sets the key to a given "SV*", taking care to set the appropriate flags to indicate the presence of an "SV*" key, and returns the same "SV*".

        SV*     HeSVKEY_set(HE* he, SV* sv)

HeUTF8

Returns whether the "char *" value returned by "HePV" is encoded in UTF−8 , doing any necessary dereferencing of possibly "SV*" keys. The value returned will be 0 or non−0, not necessarily 1 (or even a value with any low bits set), so do not blindly assign this to a "bool" variable, as "bool" may be a typedef for "char".

        char*   HeUTF8(HE* he, STRLEN len)

HeVAL

Returns the value slot (type "SV*") stored in the hash entry.

        SV*     HeVAL(HE* he)

HvNAME

Returns the package name of a stash, or NULL if "stash" isn’t a stash. See "SvSTASH", "CvSTASH".

        char*   HvNAME(HV* stash)

hv_assert

Check that a hash is in an internally consistent state.

        void    hv_assert(HV *hv)

hv_clear

Clears a hash, making it empty.

        void    hv_clear(HV* hv)

hv_clear_placeholders

Clears any placeholders from a hash. If a restricted hash has any of its keys marked as readonly and the key is subsequently deleted, the key is not actually deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags it so it will be ignored by future operations such as iterating over the hash, but will still allow the hash to have a value reassigned to the key at some future point. This function clears any such placeholder keys from the hash. See Hash::Util::lock_keys() for an example of its use.

        void    hv_clear_placeholders(HV *hv)

hv_delete

Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. The "klen" is the length of the key. The "flags" value will normally be zero; if set to G_DISCARD then NULL will be returned.

        SV*     hv_delete(HV *hv, const char *key, I32 klen, I32 flags)

hv_delete_ent

Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. The "flags" value will normally be zero; if set to G_DISCARD then NULL will be returned. "hash" can be a valid precomputed hash value, or 0 to ask for it to be computed.

        SV*     hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)

hv_exists

Returns a boolean indicating whether the specified hash key exists. The "klen" is the length of the key.

        bool    hv_exists(HV *hv, const char *key, I32 klen)

hv_exists_ent

Returns a boolean indicating whether the specified hash key exists. "hash" can be a valid precomputed hash value, or 0 to ask for it to be computed.

        bool    hv_exists_ent(HV *hv, SV *keysv, U32 hash)

hv_fetch

Returns the SV which corresponds to the specified key in the hash. The "klen" is the length of the key. If "lval" is set then the fetch will be part of a store. Check that the return value is non-null before dereferencing it to an "SV*".

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.

        SV**    hv_fetch(HV *hv, const char *key, I32 klen, I32 lval)

hv_fetchs

Like "hv_fetch", but takes a literal string instead of a string/length pair.

        SV**    hv_fetchs(HV* tb, const char* key, I32 lval)

hv_fetch_ent

Returns the hash entry which corresponds to the specified key in the hash. "hash" must be a valid precomputed hash number for the given "key", or 0 if you want the function to compute it. IF "lval" is set then the fetch will be part of a store. Make sure the return value is non-null before accessing it. The return value when "tb" is a tied hash is a pointer to a static location, so be sure to make a copy of the structure if you need to store it somewhere.

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.

        HE*     hv_fetch_ent(HV *hv, SV *keysv, I32 lval, U32 hash)

hv_iterinit

Prepares a starting point to traverse a hash table. Returns the number of keys in the hash (i.e. the same as "HvKEYS(tb)"). The return value is currently only meaningful for hashes without tie magic.

NOTE: Before version 5.004_65, "hv_iterinit" used to return the number of hash buckets that happen to be in use. If you still need that esoteric value, you can get it through the macro "HvFILL(tb)".

        I32     hv_iterinit(HV *hv)

hv_iterkey

Returns the key from the current position of the hash iterator. See "hv_iterinit".

        char*   hv_iterkey(HE* entry, I32* retlen)

hv_iterkeysv

Returns the key as an "SV*" from the current position of the hash iterator. The return value will always be a mortal copy of the key. Also see "hv_iterinit".

        SV*     hv_iterkeysv(HE* entry)

hv_iternext

Returns entries from a hash iterator. See "hv_iterinit".

You may call "hv_delete" or "hv_delete_ent" on the hash entry that the iterator currently points to, without losing your place or invalidating your iterator. Note that in this case the current entry is deleted from the hash with your iterator holding the last reference to it. Your iterator is flagged to free the entry on the next call to "hv_iternext", so you must not discard your iterator immediately else the entry will leak − call "hv_iternext" to trigger the resource deallocation.

        HE*     hv_iternext(HV *hv)

hv_iternextsv

Performs an "hv_iternext", "hv_iterkey", and "hv_iterval" in one operation.

        SV*     hv_iternextsv(HV *hv, char **key, I32 *retlen)

hv_iternext_flags

Returns entries from a hash iterator. See "hv_iterinit" and "hv_iternext". The "flags" value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is set the placeholders keys (for restricted hashes) will be returned in addition to normal keys. By default placeholders are automatically skipped over. Currently a placeholder is implemented with a value that is &Perl_sv_placeholder. Note that the implementation of placeholders and restricted hashes may change, and the implementation currently is insufficiently abstracted for any change to be tidy.

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

        HE*     hv_iternext_flags(HV *hv, I32 flags)

hv_iterval

Returns the value from the current position of the hash iterator. See "hv_iterkey".

        SV*     hv_iterval(HV *hv, HE *entry)

hv_magic

Adds magic to a hash. See "sv_magic".

        void    hv_magic(HV *hv, GV *gv, int how)

hv_scalar

Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.

        SV*     hv_scalar(HV *hv)

hv_store

Stores an SV in a hash. The hash key is specified as "key" and "klen" is the length of the key. The "hash" parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value will be NULL if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise it can be dereferenced to get the original "SV*". Note that the caller is responsible for suitably incrementing the reference count of "val" before the call, and decrementing it if the function returned NULL . Effectively a successful hv_store takes ownership of one reference to "val". This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store will own the only reference to the new SV , and your code doesn’t need to do anything further to tidy up. hv_store is not implemented as a call to hv_store_ent, and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store in preference to hv_store_ent.

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.

        SV**    hv_store(HV *hv, const char *key, I32 klen, SV *val, U32 hash)

hv_stores

Like "hv_store", but takes a literal string instead of a string/length pair and omits the hash parameter.

        SV**    hv_stores(HV* tb, const char* key, NULLOK SV* val)

hv_store_ent

Stores "val" in a hash. The hash key is specified as "key". The "hash" parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value is the new hash entry so created. It will be NULL if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise the contents of the return value can be accessed using the "He?" macros described here. Note that the caller is responsible for suitably incrementing the reference count of "val" before the call, and decrementing it if the function returned NULL . Effectively a successful hv_store_ent takes ownership of one reference to "val". This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store will own the only reference to the new SV , and your code doesn’t need to do anything further to tidy up. Note that hv_store_ent only reads the "key"; unlike "val" it does not take ownership of it, so maintaining the correct reference count on "key" is entirely the caller’s responsibility. hv_store is not implemented as a call to hv_store_ent, and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store in preference to hv_store_ent.

See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.

        HE*     hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)

hv_undef

Undefines the hash.

        void    hv_undef(HV *hv)

newHV

Creates a new HV . The reference count is set to 1.

        HV*     newHV()

mg_clear

Clear something magical that the SV represents. See "sv_magic".

        int     mg_clear(SV* sv)

mg_copy

Copies the magic from one SV to another. See "sv_magic".

        int     mg_copy(SV *sv, SV *nsv, const char *key, I32 klen)

mg_find

Finds the magic pointer for type matching the SV . See "sv_magic".

        MAGIC*  mg_find(const SV* sv, int type)

mg_free

Free any magic storage used by the SV . See "sv_magic".

        int     mg_free(SV* sv)

mg_get

Do magic after a value is retrieved from the SV . See "sv_magic".

        int     mg_get(SV* sv)

mg_length

Report on the SV ’s length. See "sv_magic".

        U32     mg_length(SV* sv)

mg_magical

Turns on the magical status of an SV . See "sv_magic".

        void    mg_magical(SV* sv)

mg_set

Do magic after a value is assigned to the SV . See "sv_magic".

        int     mg_set(SV* sv)

SvGETMAGIC

Invokes "mg_get" on an SV if it has ’get’ magic. This macro evaluates its argument more than once.

        void    SvGETMAGIC(SV* sv)

SvLOCK

Arranges for a mutual exclusion lock to be obtained on sv if a suitable module has been loaded.

        void    SvLOCK(SV* sv)

SvSETMAGIC

Invokes "mg_set" on an SV if it has ’set’ magic. This macro evaluates its argument more than once.

        void    SvSETMAGIC(SV* sv)

SvSetMagicSV

Like "SvSetSV", but does any set magic required afterwards.

        void    SvSetMagicSV(SV* dsb, SV* ssv)

SvSetMagicSV_nosteal

Like "SvSetSV_nosteal", but does any set magic required afterwards.

        void    SvSetMagicSV_nosteal(SV* dsv, SV* ssv)

SvSetSV

Calls "sv_setsv" if dsv is not the same as ssv. May evaluate arguments more than once.

        void    SvSetSV(SV* dsb, SV* ssv)

SvSetSV_nosteal

Calls a non-destructive version of "sv_setsv" if dsv is not the same as ssv. May evaluate arguments more than once.

        void    SvSetSV_nosteal(SV* dsv, SV* ssv)

SvSHARE

Arranges for sv to be shared between threads if a suitable module has been loaded.

        void    SvSHARE(SV* sv)

SvUNLOCK

Releases a mutual exclusion lock on sv if a suitable module has been loaded.

        void    SvUNLOCK(SV* sv)

Copy

The XSUB-writer’s interface to the C "memcpy" function. The "src" is the source, "dest" is the destination, "nitems" is the number of items, and "type" is the type. May fail on overlapping copies. See also "Move".

        void    Copy(void* src, void* dest, int nitems, type)

CopyD

Like "Copy" but returns dest. Useful for encouraging compilers to tail-call optimise.

        void *  CopyD(void* src, void* dest, int nitems, type)

Move

The XSUB-writer’s interface to the C "memmove" function. The "src" is the source, "dest" is the destination, "nitems" is the number of items, and "type" is the type. Can do overlapping moves. See also "Copy".

        void    Move(void* src, void* dest, int nitems, type)

MoveD

Like "Move" but returns dest. Useful for encouraging compilers to tail-call optimise.

        void *  MoveD(void* src, void* dest, int nitems, type)

Newx

The XSUB-writer’s interface to the C "malloc" function.

In 5.9.3, Newx() and friends replace the older New() API , and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG (see " PERL_MEM_LOG " in perlhack). The older API is still there for use in XS modules supporting older perls.

        void    Newx(void* ptr, int nitems, type)

Newxc

The XSUB-writer’s interface to the C "malloc" function, with cast. See also "Newx".

        void    Newxc(void* ptr, int nitems, type, cast)

Newxz

The XSUB-writer’s interface to the C "malloc" function. The allocated memory is zeroed with "memzero". See also "Newx".

        void    Newxz(void* ptr, int nitems, type)

Poison

PoisonWith(0xEF) for catching access to freed memory.

        void    Poison(void* dest, int nitems, type)

PoisonFree

PoisonWith(0xEF) for catching access to freed memory.

        void    PoisonFree(void* dest, int nitems, type)

PoisonNew

PoisonWith(0xAB) for catching access to allocated but uninitialized memory.

        void    PoisonNew(void* dest, int nitems, type)

PoisonWith

Fill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches attempts to access uninitialized memory.

        void    PoisonWith(void* dest, int nitems, type, U8 byte)

Renew

The XSUB-writer’s interface to the C "realloc" function.

        void    Renew(void* ptr, int nitems, type)

Renewc

The XSUB-writer’s interface to the C "realloc" function, with cast.

        void    Renewc(void* ptr, int nitems, type, cast)

Safefree

The XSUB-writer’s interface to the C "free" function.

        void    Safefree(void* ptr)

savepv

Perl’s version of "strdup()". Returns a pointer to a newly allocated string which is a duplicate of "pv". The size of the string is determined by "strlen()". The memory allocated for the new string can be freed with the "Safefree()" function.

        char*   savepv(const char* pv)

savepvn

Perl’s version of what "strndup()" would be if it existed. Returns a pointer to a newly allocated string which is a duplicate of the first "len" bytes from "pv", plus a trailing NUL byte. The memory allocated for the new string can be freed with the "Safefree()" function.

        char*   savepvn(const char* pv, I32 len)

savepvs

Like "savepvn", but takes a literal string instead of a string/length pair.

        char*   savepvs(const char* s)

savesharedpv

A version of "savepv()" which allocates the duplicate string in memory which is shared between threads.

        char*   savesharedpv(const char* pv)

savesharedpvn

A version of "savepvn()" which allocates the duplicate string in memory which is shared between threads. (With the specific difference that a NULL pointer is not acceptable)

        char*   savesharedpvn(const char *const pv, const STRLEN len)

savesvpv

A version of "savepv()"/"savepvn()" which gets the string to duplicate from the passed in SV using "SvPV()"

        char*   savesvpv(SV* sv)

StructCopy

This is an architecture-independent macro to copy one structure to another.

        void    StructCopy(type src, type dest, type)

Zero

The XSUB-writer’s interface to the C "memzero" function. The "dest" is the destination, "nitems" is the number of items, and "type" is the type.

        void    Zero(void* dest, int nitems, type)

ZeroD

Like "Zero" but returns dest. Useful for encouraging compilers to tail-call optimise.

        void *  ZeroD(void* dest, int nitems, type)

fbm_compile

Analyses the string in order to make fast searches on it using fbm_instr() -- the Boyer-Moore algorithm.

        void    fbm_compile(SV* sv, U32 flags)

fbm_instr

Returns the location of the SV in the string delimited by "str" and "strend". It returns "NULL" if the string can’t be found. The "sv" does not have to be fbm_compiled, but the search will not be as fast then.

        char*   fbm_instr(unsigned char* big, unsigned char* bigend, SV* littlestr, U32 flags)

form

Takes a sprintf-style format pattern and conventional (non-SV) arguments and returns the formatted string.

    (char *) Perl_form(pTHX_ const char* pat, ...)

can be used any place a string (char *) is required:

    char * s = Perl_form("%d.%d",major,minor);

Uses a single private buffer so if you want to format several strings you must explicitly copy the earlier strings away (and free the copies when you are done).

        char*   form(const char* pat, ...)

getcwd_sv

Fill the sv with current working directory

        int     getcwd_sv(SV* sv)

my_snprintf

The C library "snprintf" functionality, if available and standards-compliant (uses "vsnprintf", actually). However, if the "vsnprintf" is not available, will unfortunately use the unsafe "vsprintf" which can overrun the buffer (there is an overrun check, but that may be too late). Consider using "sv_vcatpvf" instead, or getting "vsnprintf".

        int     my_snprintf(char *buffer, const Size_t len, const char *format, ...)

my_sprintf

The C library "sprintf", wrapped if necessary, to ensure that it will return the length of the string written to the buffer. Only rare pre-ANSI systems need the wrapper function − usually this is a direct call to "sprintf".

        int     my_sprintf(char *buffer, const char *pat, ...)

my_vsnprintf

The C library "vsnprintf" if available and standards-compliant. However, if if the "vsnprintf" is not available, will unfortunately use the unsafe "vsprintf" which can overrun the buffer (there is an overrun check, but that may be too late). Consider using "sv_vcatpvf" instead, or getting "vsnprintf".

        int     my_vsnprintf(char *buffer, const Size_t len, const char *format, va_list ap)

new_version

Returns a new version object based on the passed in SV:

    SV *sv = new_version(SV *ver);

Does not alter the passed in ver SV . See "upg_version" if you want to upgrade the SV .

        SV*     new_version(SV *ver)

scan_version

Returns a pointer to the next character after the parsed version string, as well as upgrading the passed in SV to an RV .

Function must be called with an already existing SV like

    sv = newSV(0);
    s = scan_version(s, SV *sv, bool qv);

Performs some preprocessing to the string to ensure that it has the correct characteristics of a version. Flags the object if it contains an underscore (which denotes this is an alpha version). The boolean qv denotes that the version should be interpreted as if it had multiple decimals, even if it doesn’t.

        const char*     scan_version(const char *s, SV *rv, bool qv)

strEQ

Test two strings to see if they are equal. Returns true or false.

        bool    strEQ(char* s1, char* s2)

strGE

Test two strings to see if the first, "s1", is greater than or equal to the second, "s2". Returns true or false.

        bool    strGE(char* s1, char* s2)

strGT

Test two strings to see if the first, "s1", is greater than the second, "s2". Returns true or false.

        bool    strGT(char* s1, char* s2)

strLE

Test two strings to see if the first, "s1", is less than or equal to the second, "s2". Returns true or false.

        bool    strLE(char* s1, char* s2)

strLT

Test two strings to see if the first, "s1", is less than the second, "s2". Returns true or false.

        bool    strLT(char* s1, char* s2)

strNE

Test two strings to see if they are different. Returns true or false.

        bool    strNE(char* s1, char* s2)

strnEQ

Test two strings to see if they are equal. The "len" parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for "strncmp").

        bool    strnEQ(char* s1, char* s2, STRLEN len)

strnNE

Test two strings to see if they are different. The "len" parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for "strncmp").

        bool    strnNE(char* s1, char* s2, STRLEN len)

sv_destroyable

Dummy routine which reports that object can be destroyed when there is no sharing module present. It ignores its single SV argument, and returns ’true’. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.

        bool    sv_destroyable(SV *sv)

sv_nosharing

Dummy routine which "shares" an SV when there is no sharing module present. Or "locks" it. Or "unlocks" it. In other words, ignores its single SV argument. Exists to avoid test for a NULL function pointer and because it could potentially warn under some level of strict-ness.

        void    sv_nosharing(SV *sv)

upg_version

In-place upgrade of the supplied SV to a version object.

    SV *sv = upg_version(SV *sv, bool qv);

Returns a pointer to the upgraded SV . Set the boolean qv if you want to force this SV to be interpreted as an "extended" version.

        SV*     upg_version(SV *ver, bool qv)

vcmp

Version object aware cmp. Both operands must already have been converted into version objects.

        int     vcmp(SV *lhv, SV *rhv)

vnormal

Accepts a version object and returns the normalized string representation. Call like:

    sv = vnormal(rv);

NOTE: you can pass either the object directly or the SV contained within the RV .

        SV*     vnormal(SV *vs)

vnumify

Accepts a version object and returns the normalized floating point representation. Call like:

    sv = vnumify(rv);

NOTE: you can pass either the object directly or the SV contained within the RV .

        SV*     vnumify(SV *vs)

vstringify

In order to maintain maximum compatibility with earlier versions of Perl, this function will return either the floating point notation or the multiple dotted notation, depending on whether the original version contained 1 or more dots, respectively

        SV*     vstringify(SV *vs)

vverify

Validates that the SV contains a valid version object.

    bool vverify(SV *vobj);

Note that it only confirms the bare minimum structure (so as not to get confused by derived classes which may contain additional hash entries):

        bool    vverify(SV *vs)

mro_get_linear_isa

Returns either "mro_get_linear_isa_c3" or "mro_get_linear_isa_dfs" for the given stash, dependant upon which MRO is in effect for that stash. The return value is a read-only AV*.

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(HV* stash)

mro_method_changed_in

Invalidates method caching on any child classes of the given stash, so that they might notice the changes in this one.

Ideally, all instances of "PL_sub_generation++" in perl source outside of "mro.c" should be replaced by calls to this.

Perl automatically handles most of the common ways a method might be redefined. However, there are a few ways you could change a method in a stash without the cache code noticing, in which case you need to call this method afterwards:

1) Directly manipulating the stash HV entries from XS code.

2) Assigning a reference to a readonly scalar constant into a stash entry in order to create a constant subroutine (like constant.pm does).

This same method is available from pure perl via, "mro::method_changed_in(classname)".

        void    mro_method_changed_in(HV* stash)

dMULTICALL

Declare local variables for a multicall. See "Lightweight Callbacks" in perlcall.

                dMULTICALL;

MULTICALL

Make a lightweight callback. See "Lightweight Callbacks" in perlcall.

                MULTICALL;

POP_MULTICALL

Closing bracket for a lightweight callback. See "Lightweight Callbacks" in perlcall.

                POP_MULTICALL;

PUSH_MULTICALL

Opening bracket for a lightweight callback. See "Lightweight Callbacks" in perlcall.

                PUSH_MULTICALL;

grok_bin

converts a string representing a binary number to numeric form.

On entry start and *len give the string to scan, *flags gives conversion flags, and result should be NULL or a pointer to an NV . The scan stops at the end of the string, or the first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set in *flags, encountering an invalid character will also trigger a warning. On return *len is set to the length of the scanned string, and *flags gives output flags.

If the value is <= "UV_MAX" it is returned as a UV , the output flags are clear, and nothing is written to *result. If the value is > UV_MAX "grok_bin" returns UV_MAX , sets "PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the value is discarded if result is NULL ).

The binary number may optionally be prefixed with "0b" or "b" unless "PERL_SCAN_DISALLOW_PREFIX" is set in *flags on entry. If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the binary number may use ’_’ characters to separate digits.

        UV      grok_bin(const char* start, STRLEN* len_p, I32* flags, NV *result)

grok_hex

converts a string representing a hex number to numeric form.

On entry start and *len give the string to scan, *flags gives conversion flags, and result should be NULL or a pointer to an NV . The scan stops at the end of the string, or the first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set in *flags, encountering an invalid character will also trigger a warning. On return *len is set to the length of the scanned string, and *flags gives output flags.

If the value is <= UV_MAX it is returned as a UV , the output flags are clear, and nothing is written to *result. If the value is > UV_MAX "grok_hex" returns UV_MAX , sets "PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the value is discarded if result is NULL ).

The hex number may optionally be prefixed with "0x" or "x" unless "PERL_SCAN_DISALLOW_PREFIX" is set in *flags on entry. If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the hex number may use ’_’ characters to separate digits.

        UV      grok_hex(const char* start, STRLEN* len_p, I32* flags, NV *result)

grok_number

Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination of IS_NUMBER_IN_UV , IS_NUMBER_GREATER_THAN_UV_MAX , IS_NUMBER_NOT_INT , IS_NUMBER_NEG , IS_NUMBER_INFINITY , IS_NUMBER_NAN (defined in perl.h).

If the value of the number can fit an in UV , it is returned in the *valuep IS_NUMBER_IN_UV will be set to indicate that *valuep is valid, IS_NUMBER_IN_UV will never be set unless *valuep is valid, but *valuep may have been assigned to during processing even though IS_NUMBER_IN_UV is not set on return. If valuep is NULL , IS_NUMBER_IN_UV will be set for the same cases as when valuep is non-NULL, but no actual assignment (or SEGV ) will occur.

IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were seen (in which case *valuep gives the true value truncated to an integer), and IS_NUMBER_NEG if the number is negative (in which case *valuep holds the absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the number is larger than a UV .

        int     grok_number(const char *pv, STRLEN len, UV *valuep)

grok_numeric_radix

Scan and skip for a numeric decimal separator (radix).

        bool    grok_numeric_radix(const char **sp, const char *send)

grok_oct

converts a string representing an octal number to numeric form.

On entry start and *len give the string to scan, *flags gives conversion flags, and result should be NULL or a pointer to an NV . The scan stops at the end of the string, or the first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set in *flags, encountering an invalid character will also trigger a warning. On return *len is set to the length of the scanned string, and *flags gives output flags.

If the value is <= UV_MAX it is returned as a UV , the output flags are clear, and nothing is written to *result. If the value is > UV_MAX "grok_oct" returns UV_MAX , sets "PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the value is discarded if result is NULL ).

If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the octal number may use ’_’ characters to separate digits.

        UV      grok_oct(const char* start, STRLEN* len_p, I32* flags, NV *result)

Perl_signbit

Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.

If Configure detects this system has a signbit() that will work with our NVs, then we just use it via the #define in perl.h. Otherwise, fall back on this implementation. As a first pass, this gets everything right except −0.0. Alas, catching −0.0 is the main use for this function, so this is not too helpful yet. Still, at least we have the scaffolding in place to support other systems, should that prove useful.

Configure notes: This function is called ’Perl_signbit’ instead of a plain ’signbit’ because it is easy to imagine a system having a signbit() function or macro that doesn’t happen to work with our particular choice of NVs. We shouldn’t just re−#define signbit as Perl_signbit and expect the standard system headers to be happy. Also, this is a no-context function (no pTHX_) because Perl_signbit() is usually re−#defined in perl.h as a simple macro call to the system’s signbit(). Users should just always call Perl_signbit().

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

        int     Perl_signbit(NV f)

scan_bin

For backwards compatibility. Use "grok_bin" instead.

        NV      scan_bin(const char* start, STRLEN len, STRLEN* retlen)

scan_hex

For backwards compatibility. Use "grok_hex" instead.

        NV      scan_hex(const char* start, STRLEN len, STRLEN* retlen)

scan_oct

For backwards compatibility. Use "grok_oct" instead.

        NV      scan_oct(const char* start, STRLEN len, STRLEN* retlen)

cv_const_sv

If "cv" is a constant sub eligible for inlining. returns the constant value returned by the sub. Otherwise, returns NULL .

Constant subs can be created with "newCONSTSUB" or as described in "Constant Functions" in perlsub.

        SV*     cv_const_sv(CV* cv)

newCONSTSUB

Creates a constant sub equivalent to Perl "sub FOO () { 123 }" which is eligible for inlining at compile-time.

        CV*     newCONSTSUB(HV* stash, const char* name, SV* sv)

newXS

Used by "xsubpp" to hook up XSUBs as Perl subs. filename needs to be static storage, as it is used directly as CvFILE(), without a copy being made.

pad_sv

Get the value at offset po in the current pad. Use macro PAD_SV instead of calling this function directly.

        SV*     pad_sv(PADOFFSET po)

PL_modglobal

"PL_modglobal" is a general purpose, interpreter global HV for use by extensions that need to keep information on a per-interpreter basis. In a pinch, it can also be used as a symbol table for extensions to share data among each other. It is a good idea to use keys prefixed by the package name of the extension that owns the data.

        HV*     PL_modglobal

PL_na

A convenience variable which is typically used with "SvPV" when one doesn’t care about the length of the string. It is usually more efficient to either declare a local variable and use that instead or to use the "SvPV_nolen" macro.

        STRLEN  PL_na

PL_sv_no

This is the "false" SV . See "PL_sv_yes". Always refer to this as &PL_sv_no.

        SV      PL_sv_no

PL_sv_undef

This is the "undef" SV . Always refer to this as &PL_sv_undef.

        SV      PL_sv_undef

PL_sv_yes

This is the "true" SV . See "PL_sv_no". Always refer to this as &PL_sv_yes.

        SV      PL_sv_yes

SvRX

Convenience macro to get the REGEXP from a SV . This is approximately equivalent to the following snippet:

    if (SvMAGICAL(sv))
        mg_get(sv);
    if (SvROK(sv) &&
        (tmpsv = (SV*)SvRV(sv)) &&
        SvTYPE(tmpsv) == SVt_PVMG &&
        (tmpmg = mg_find(tmpsv, PERL_MAGIC_qr)))
    {
        return (REGEXP *)tmpmg−>mg_obj;
    }

NULL will be returned if a REGEXP* is not found.

        REGEXP *        SvRX(SV *sv)

SvRXOK

Returns a boolean indicating whether the SV contains qr magic (PERL_MAGIC_qr).

If you want to do something with the REGEXP* later use SvRX instead and check for NULL .

        bool    SvRXOK(SV* sv)

dXCPT

Set up necessary local variables for exception handling. See "Exception Handling" in perlguts.

                dXCPT;

XCPT_CATCH

Introduces a catch block. See "Exception Handling" in perlguts.

XCPT_RETHROW

Rethrows a previously caught exception. See "Exception Handling" in perlguts.

                XCPT_RETHROW;

XCPT_TRY_END

Ends a try block. See "Exception Handling" in perlguts.

XCPT_TRY_START

Starts a try block. See "Exception Handling" in perlguts.

dMARK

Declare a stack marker variable, "mark", for the XSUB . See "MARK" and "dORIGMARK".

                dMARK;

dORIGMARK

Saves the original stack mark for the XSUB . See "ORIGMARK".

                dORIGMARK;

dSP

Declares a local copy of perl’s stack pointer for the XSUB , available via the "SP" macro. See "SP".

                dSP;

EXTEND

Used to extend the argument stack for an XSUB ’s return values. Once used, guarantees that there is room for at least "nitems" to be pushed onto the stack.

        void    EXTEND(SP, int nitems)

MARK

Stack marker variable for the XSUB . See "dMARK".

mPUSHi

Push an integer onto the stack. The stack must have room for this element. Does not use "TARG". See also "PUSHi", "mXPUSHi" and "XPUSHi".

        void    mPUSHi(IV iv)

mPUSHn

Push a double onto the stack. The stack must have room for this element. Does not use "TARG". See also "PUSHn", "mXPUSHn" and "XPUSHn".

        void    mPUSHn(NV nv)

mPUSHp

Push a string onto the stack. The stack must have room for this element. The "len" indicates the length of the string. Does not use "TARG". See also "PUSHp", "mXPUSHp" and "XPUSHp".

        void    mPUSHp(char* str, STRLEN len)

mPUSHs

Push an SV onto the stack and mortalizes the SV . The stack must have room for this element. Does not use "TARG". See also "PUSHs" and "mXPUSHs".

        void    mPUSHs(SV* sv)

mPUSHu

Push an unsigned integer onto the stack. The stack must have room for this element. Does not use "TARG". See also "PUSHu", "mXPUSHu" and "XPUSHu".

        void    mPUSHu(UV uv)

mXPUSHi

Push an integer onto the stack, extending the stack if necessary. Does not use "TARG". See also "XPUSHi", "mPUSHi" and "PUSHi".

        void    mXPUSHi(IV iv)

mXPUSHn

Push a double onto the stack, extending the stack if necessary. Does not use "TARG". See also "XPUSHn", "mPUSHn" and "PUSHn".

        void    mXPUSHn(NV nv)

mXPUSHp

Push a string onto the stack, extending the stack if necessary. The "len" indicates the length of the string. Does not use "TARG". See also "XPUSHp", "mPUSHp" and "PUSHp".

        void    mXPUSHp(char* str, STRLEN len)

mXPUSHs

Push an SV onto the stack, extending the stack if necessary and mortalizes the SV . Does not use "TARG". See also "XPUSHs" and "mPUSHs".

        void    mXPUSHs(SV* sv)

mXPUSHu

Push an unsigned integer onto the stack, extending the stack if necessary. Does not use "TARG". See also "XPUSHu", "mPUSHu" and "PUSHu".

        void    mXPUSHu(UV uv)

ORIGMARK

The original stack mark for the XSUB . See "dORIGMARK".

POPi

Pops an integer off the stack.

        IV      POPi

POPl

Pops a long off the stack.

        long    POPl

POPn

Pops a double off the stack.

        NV      POPn

POPp

Pops a string off the stack. Deprecated. New code should use POPpx.

        char*   POPp

POPpbytex

Pops a string off the stack which must consist of bytes i.e. characters < 256.

        char*   POPpbytex

POPpx

Pops a string off the stack.

        char*   POPpx

POPs

Pops an SV off the stack.

        SV*     POPs

PUSHi

Push an integer onto the stack. The stack must have room for this element. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mPUSHi" instead. See also "XPUSHi" and "mXPUSHi".

        void    PUSHi(IV iv)

PUSHMARK

Opening bracket for arguments on a callback. See "PUTBACK" and perlcall.

        void    PUSHMARK(SP)

PUSHmortal

Push a new mortal SV onto the stack. The stack must have room for this element. Does not use "TARG". See also "PUSHs", "XPUSHmortal" and "XPUSHs".

        void    PUSHmortal()

PUSHn

Push a double onto the stack. The stack must have room for this element. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mPUSHn" instead. See also "XPUSHn" and "mXPUSHn".

        void    PUSHn(NV nv)

PUSHp

Push a string onto the stack. The stack must have room for this element. The "len" indicates the length of the string. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mPUSHp" instead. See also "XPUSHp" and "mXPUSHp".

        void    PUSHp(char* str, STRLEN len)

PUSHs

Push an SV onto the stack. The stack must have room for this element. Does not handle ’set’ magic. Does not use "TARG". See also "PUSHmortal", "XPUSHs" and "XPUSHmortal".

        void    PUSHs(SV* sv)

PUSHu

Push an unsigned integer onto the stack. The stack must have room for this element. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mPUSHu" instead. See also "XPUSHu" and "mXPUSHu".

        void    PUSHu(UV uv)

PUTBACK

Closing bracket for XSUB arguments. This is usually handled by "xsubpp". See "PUSHMARK" and perlcall for other uses.

                PUTBACK;

SP

Stack pointer. This is usually handled by "xsubpp". See "dSP" and "SPAGAIN".

SPAGAIN

Refetch the stack pointer. Used after a callback. See perlcall.

                SPAGAIN;

XPUSHi

Push an integer onto the stack, extending the stack if necessary. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mXPUSHi" instead. See also "PUSHi" and "mPUSHi".

        void    XPUSHi(IV iv)

XPUSHmortal

Push a new mortal SV onto the stack, extending the stack if necessary. Does not use "TARG". See also "XPUSHs", "PUSHmortal" and "PUSHs".

        void    XPUSHmortal()

XPUSHn

Push a double onto the stack, extending the stack if necessary. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mXPUSHn" instead. See also "PUSHn" and "mPUSHn".

        void    XPUSHn(NV nv)

XPUSHp

Push a string onto the stack, extending the stack if necessary. The "len" indicates the length of the string. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mXPUSHp" instead. See also "PUSHp" and "mPUSHp".

        void    XPUSHp(char* str, STRLEN len)

XPUSHs

Push an SV onto the stack, extending the stack if necessary. Does not handle ’set’ magic. Does not use "TARG". See also "XPUSHmortal", "PUSHs" and "PUSHmortal".

        void    XPUSHs(SV* sv)

XPUSHu

Push an unsigned integer onto the stack, extending the stack if necessary. Handles ’set’ magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple "TARG"−oriented macros to return lists from XSUB ’s − see "mXPUSHu" instead. See also "PUSHu" and "mPUSHu".

        void    XPUSHu(UV uv)

XSRETURN

Return from XSUB , indicating number of items on the stack. This is usually handled by "xsubpp".

        void    XSRETURN(int nitems)

XSRETURN_EMPTY

Return an empty list from an XSUB immediately.

                XSRETURN_EMPTY;

XSRETURN_IV

Return an integer from an XSUB immediately. Uses "XST_mIV".

        void    XSRETURN_IV(IV iv)

XSRETURN_NO

Return &PL_sv_no from an XSUB immediately. Uses "XST_mNO".

                XSRETURN_NO;

XSRETURN_NV

Return a double from an XSUB immediately. Uses "XST_mNV".

        void    XSRETURN_NV(NV nv)

XSRETURN_PV

Return a copy of a string from an XSUB immediately. Uses "XST_mPV".

        void    XSRETURN_PV(char* str)

XSRETURN_UNDEF

Return &PL_sv_undef from an XSUB immediately. Uses "XST_mUNDEF".

                XSRETURN_UNDEF;

XSRETURN_UV

Return an integer from an XSUB immediately. Uses "XST_mUV".

        void    XSRETURN_UV(IV uv)

XSRETURN_YES

Return &PL_sv_yes from an XSUB immediately. Uses "XST_mYES".

                XSRETURN_YES;

XST_mIV

Place an integer into the specified position "pos" on the stack. The value is stored in a new mortal SV .

        void    XST_mIV(int pos, IV iv)

XST_mNO

Place &PL_sv_no into the specified position "pos" on the stack.

        void    XST_mNO(int pos)

XST_mNV

Place a double into the specified position "pos" on the stack. The value is stored in a new mortal SV .

        void    XST_mNV(int pos, NV nv)

XST_mPV

Place a copy of a string into the specified position "pos" on the stack. The value is stored in a new mortal SV .

        void    XST_mPV(int pos, char* str)

XST_mUNDEF

Place &PL_sv_undef into the specified position "pos" on the stack.

        void    XST_mUNDEF(int pos)

XST_mYES

Place &PL_sv_yes into the specified position "pos" on the stack.

        void    XST_mYES(int pos)

svtype

An enum of flags for Perl types. These are found in the file sv.h in the "svtype" enum. Test these flags with the "SvTYPE" macro.

SVt_IV

Integer type flag for scalars. See "svtype".

SVt_NV

Double type flag for scalars. See "svtype".

SVt_PV

Pointer type flag for scalars. See "svtype".

SVt_PVAV

Type flag for arrays. See "svtype".

SVt_PVCV

Type flag for code refs. See "svtype".

SVt_PVHV

Type flag for hashes. See "svtype".

SVt_PVMG

Type flag for blessed scalars. See "svtype".

croak_xs_usage

A specialised variant of "croak()" for emitting the usage message for xsubs

    croak_xs_usage(cv, "eee_yow");

works out the package name and subroutine name from "cv", and then calls "croak()". Hence if "cv" is &ouch::awk, it would call "croak" as:

    Perl_croak(aTHX_ "Usage %s::%s(%s)", "ouch" "awk", "eee_yow");

        void    croak_xs_usage(const CV *const cv, const char *const params)

get_sv

Returns the SV of the specified Perl scalar. "flags" are passed to "gv_fetchpv". If "GV_ADD" is set and the Perl variable does not exist then it will be created. If "flags" is zero and the variable does not exist then NULL is returned.

NOTE: the perl_ form of this function is deprecated.

        SV*     get_sv(const char *name, I32 flags)

newRV_inc

Creates an RV wrapper for an SV . The reference count for the original SV is incremented.

        SV*     newRV_inc(SV* sv)

newSVpvn_utf8

Creates a new SV and copies a string into it. If utf8 is true, calls "SvUTF8_on" on the new SV . Implemented as a wrapper around "newSVpvn_flags".

        SV*     newSVpvn_utf8(NULLOK const char* s, STRLEN len, U32 utf8)

SvCUR

Returns the length of the string which is in the SV . See "SvLEN".

        STRLEN  SvCUR(SV* sv)

SvCUR_set

Set the current length of the string which is in the SV . See "SvCUR" and "SvIV_set".

        void    SvCUR_set(SV* sv, STRLEN len)

SvEND

Returns a pointer to the last character in the string which is in the SV . See "SvCUR". Access the character as *(SvEND(sv)).

        char*   SvEND(SV* sv)

SvGAMAGIC

Returns true if the SV has get magic or overloading. If either is true then the scalar is active data, and has the potential to return a new value every time it is accessed. Hence you must be careful to only read it once per user logical operation and work with that returned value. If neither is true then the scalar’s value cannot change unless written to.

        U32     SvGAMAGIC(SV* sv)

SvGROW

Expands the character buffer in the SV so that it has room for the indicated number of bytes (remember to reserve space for an extra trailing NUL character). Calls "sv_grow" to perform the expansion if necessary. Returns a pointer to the character buffer.

        char *  SvGROW(SV* sv, STRLEN len)

SvIOK

Returns a U32 value indicating whether the SV contains an integer.

        U32     SvIOK(SV* sv)

SvIOKp

Returns a U32 value indicating whether the SV contains an integer. Checks the private setting. Use "SvIOK" instead.

        U32     SvIOKp(SV* sv)

SvIOK_notUV

Returns a boolean indicating whether the SV contains a signed integer.

        bool    SvIOK_notUV(SV* sv)

SvIOK_off

Unsets the IV status of an SV .

        void    SvIOK_off(SV* sv)

SvIOK_on

Tells an SV that it is an integer.

        void    SvIOK_on(SV* sv)

SvIOK_only

Tells an SV that it is an integer and disables all other OK bits.

        void    SvIOK_only(SV* sv)

SvIOK_only_UV

Tells and SV that it is an unsigned integer and disables all other OK bits.

        void    SvIOK_only_UV(SV* sv)

SvIOK_UV

Returns a boolean indicating whether the SV contains an unsigned integer.

        bool    SvIOK_UV(SV* sv)

SvIsCOW

Returns a boolean indicating whether the SV is Copy-On-Write. (either shared hash key scalars, or full Copy On Write scalars if 5.9.0 is configured for COW )

        bool    SvIsCOW(SV* sv)

SvIsCOW_shared_hash

Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.

        bool    SvIsCOW_shared_hash(SV* sv)

SvIV

Coerces the given SV to an integer and returns it. See "SvIVx" for a version which guarantees to evaluate sv only once.

        IV      SvIV(SV* sv)

SvIVX

Returns the raw value in the SV ’s IV slot, without checks or conversions. Only use when you are sure SvIOK is true. See also "SvIV()".

        IV      SvIVX(SV* sv)

SvIVx

Coerces the given SV to an integer and returns it. Guarantees to evaluate "sv" only once. Only use this if "sv" is an expression with side effects, otherwise use the more efficient "SvIV".

        IV      SvIVx(SV* sv)

SvIV_nomg

Like "SvIV" but doesn’t process magic.

        IV      SvIV_nomg(SV* sv)

SvIV_set

Set the value of the IV pointer in sv to val. It is possible to perform the same function of this macro with an lvalue assignment to "SvIVX". With future Perls, however, it will be more efficient to use "SvIV_set" instead of the lvalue assignment to "SvIVX".

        void    SvIV_set(SV* sv, IV val)

SvLEN

Returns the size of the string buffer in the SV , not including any part attributable to "SvOOK". See "SvCUR".

        STRLEN  SvLEN(SV* sv)

SvLEN_set

Set the actual length of the string which is in the SV . See "SvIV_set".

        void    SvLEN_set(SV* sv, STRLEN len)

SvMAGIC_set

Set the value of the MAGIC pointer in sv to val. See "SvIV_set".

        void    SvMAGIC_set(SV* sv, MAGIC* val)

SvNIOK

Returns a U32 value indicating whether the SV contains a number, integer or double.

        U32     SvNIOK(SV* sv)

SvNIOKp

Returns a U32 value indicating whether the SV contains a number, integer or double. Checks the private setting. Use "SvNIOK" instead.

        U32     SvNIOKp(SV* sv)

SvNIOK_off

Unsets the NV/IV status of an SV .

        void    SvNIOK_off(SV* sv)

SvNOK

Returns a U32 value indicating whether the SV contains a double.

        U32     SvNOK(SV* sv)

SvNOKp

Returns a U32 value indicating whether the SV contains a double. Checks the private setting. Use "SvNOK" instead.

        U32     SvNOKp(SV* sv)

SvNOK_off

Unsets the NV status of an SV .

        void    SvNOK_off(SV* sv)

SvNOK_on

Tells an SV that it is a double.

        void    SvNOK_on(SV* sv)

SvNOK_only

Tells an SV that it is a double and disables all other OK bits.

        void    SvNOK_only(SV* sv)

SvNV

Coerce the given SV to a double and return it. See "SvNVx" for a version which guarantees to evaluate sv only once.

        NV      SvNV(SV* sv)

SvNVX

Returns the raw value in the SV ’s NV slot, without checks or conversions. Only use when you are sure SvNOK is true. See also "SvNV()".

        NV      SvNVX(SV* sv)

SvNVx

Coerces the given SV to a double and returns it. Guarantees to evaluate "sv" only once. Only use this if "sv" is an expression with side effects, otherwise use the more efficient "SvNV".

        NV      SvNVx(SV* sv)

SvNV_set

Set the value of the NV pointer in sv to val. See "SvIV_set".

        void    SvNV_set(SV* sv, NV val)

SvOK

Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.

        U32     SvOK(SV* sv)

SvOOK

Returns a U32 indicating whether the SvIVX is a valid offset value for the SvPVX. This hack is used internally to speed up removal of characters from the beginning of a SvPV. When SvOOK is true, then the start of the allocated string buffer is really (SvPVX − SvIVX).

        U32     SvOOK(SV* sv)

SvPOK

Returns a U32 value indicating whether the SV contains a character string.

        U32     SvPOK(SV* sv)

SvPOKp

Returns a U32 value indicating whether the SV contains a character string. Checks the private setting. Use "SvPOK" instead.

        U32     SvPOKp(SV* sv)

SvPOK_off

Unsets the PV status of an SV .

        void    SvPOK_off(SV* sv)

SvPOK_on

Tells an SV that it is a string.

        void    SvPOK_on(SV* sv)

SvPOK_only

Tells an SV that it is a string and disables all other OK bits. Will also turn off the UTF−8 status.

        void    SvPOK_only(SV* sv)

SvPOK_only_UTF8

Tells an SV that it is a string and disables all other OK bits, and leaves the UTF−8 status as it was.

        void    SvPOK_only_UTF8(SV* sv)

SvPV

Returns a pointer to the string in the SV , or a stringified form of the SV if the SV does not contain a string. The SV may cache the stringified version becoming "SvPOK". Handles ’get’ magic. See also "SvPVx" for a version which guarantees to evaluate sv only once.

        char*   SvPV(SV* sv, STRLEN len)

SvPVbyte

Like "SvPV", but converts sv to byte representation first if necessary.

        char*   SvPVbyte(SV* sv, STRLEN len)

SvPVbytex

Like "SvPV", but converts sv to byte representation first if necessary. Guarantees to evaluate sv only once; use the more efficient "SvPVbyte" otherwise.

        char*   SvPVbytex(SV* sv, STRLEN len)

SvPVbytex_force

Like "SvPV_force", but converts sv to byte representation first if necessary. Guarantees to evaluate sv only once; use the more efficient "SvPVbyte_force" otherwise.

        char*   SvPVbytex_force(SV* sv, STRLEN len)

SvPVbyte_force

Like "SvPV_force", but converts sv to byte representation first if necessary.

        char*   SvPVbyte_force(SV* sv, STRLEN len)

SvPVbyte_nolen

Like "SvPV_nolen", but converts sv to byte representation first if necessary.

        char*   SvPVbyte_nolen(SV* sv)

SvPVutf8

Like "SvPV", but converts sv to utf8 first if necessary.

        char*   SvPVutf8(SV* sv, STRLEN len)

SvPVutf8x

Like "SvPV", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficient "SvPVutf8" otherwise.

        char*   SvPVutf8x(SV* sv, STRLEN len)

SvPVutf8x_force

Like "SvPV_force", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficient "SvPVutf8_force" otherwise.

        char*   SvPVutf8x_force(SV* sv, STRLEN len)

SvPVutf8_force

Like "SvPV_force", but converts sv to utf8 first if necessary.

        char*   SvPVutf8_force(SV* sv, STRLEN len)

SvPVutf8_nolen

Like "SvPV_nolen", but converts sv to utf8 first if necessary.

        char*   SvPVutf8_nolen(SV* sv)

SvPVX

Returns a pointer to the physical string in the SV . The SV must contain a string.

        char*   SvPVX(SV* sv)

SvPVx

A version of "SvPV" which guarantees to evaluate "sv" only once. Only use this if "sv" is an expression with side effects, otherwise use the more efficient "SvPVX".

        char*   SvPVx(SV* sv, STRLEN len)

SvPV_force

Like "SvPV" but will force the SV into containing just a string ("SvPOK_only"). You want force if you are going to update the "SvPVX" directly.

        char*   SvPV_force(SV* sv, STRLEN len)

SvPV_force_nomg

Like "SvPV" but will force the SV into containing just a string ("SvPOK_only"). You want force if you are going to update the "SvPVX" directly. Doesn’t process magic.

        char*   SvPV_force_nomg(SV* sv, STRLEN len)

SvPV_nolen

Returns a pointer to the string in the SV , or a stringified form of the SV if the SV does not contain a string. The SV may cache the stringified form becoming "SvPOK". Handles ’get’ magic.

        char*   SvPV_nolen(SV* sv)

SvPV_nomg

Like "SvPV" but doesn’t process magic.

        char*   SvPV_nomg(SV* sv, STRLEN len)

SvPV_set

Set the value of the PV pointer in sv to val. See "SvIV_set".

        void    SvPV_set(SV* sv, char* val)

SvREFCNT

Returns the value of the object’s reference count.

        U32     SvREFCNT(SV* sv)

SvREFCNT_dec

Decrements the reference count of the given SV .

        void    SvREFCNT_dec(SV* sv)

SvREFCNT_inc

Increments the reference count of the given SV .

All of the following SvREFCNT_inc* macros are optimized versions of SvREFCNT_inc, and can be replaced with SvREFCNT_inc.

        SV*     SvREFCNT_inc(SV* sv)

SvREFCNT_inc_NN

Same as SvREFCNT_inc, but can only be used if you know sv is not NULL . Since we don’t have to check the NULLness, it’s faster and smaller.

        SV*     SvREFCNT_inc_NN(SV* sv)

SvREFCNT_inc_simple

Same as SvREFCNT_inc, but can only be used with expressions without side effects. Since we don’t have to store a temporary value, it’s faster.

        SV*     SvREFCNT_inc_simple(SV* sv)

SvREFCNT_inc_simple_NN

Same as SvREFCNT_inc_simple, but can only be used if you know sv is not NULL . Since we don’t have to check the NULLness, it’s faster and smaller.

        SV*     SvREFCNT_inc_simple_NN(SV* sv)

SvREFCNT_inc_simple_void

Same as SvREFCNT_inc_simple, but can only be used if you don’t need the return value. The macro doesn’t need to return a meaningful value.

        void    SvREFCNT_inc_simple_void(SV* sv)

SvREFCNT_inc_simple_void_NN

Same as SvREFCNT_inc, but can only be used if you don’t need the return value, and you know that sv is not NULL . The macro doesn’t need to return a meaningful value, or check for NULLness, so it’s smaller and faster.

        void    SvREFCNT_inc_simple_void_NN(SV* sv)

SvREFCNT_inc_void

Same as SvREFCNT_inc, but can only be used if you don’t need the return value. The macro doesn’t need to return a meaningful value.

        void    SvREFCNT_inc_void(SV* sv)

SvREFCNT_inc_void_NN

Same as SvREFCNT_inc, but can only be used if you don’t need the return value, and you know that sv is not NULL . The macro doesn’t need to return a meaningful value, or check for NULLness, so it’s smaller and faster.

        void    SvREFCNT_inc_void_NN(SV* sv)

SvROK

Tests if the SV is an RV .

        U32     SvROK(SV* sv)

SvROK_off

Unsets the RV status of an SV .

        void    SvROK_off(SV* sv)

SvROK_on

Tells an SV that it is an RV .

        void    SvROK_on(SV* sv)

SvRV

Dereferences an RV to return the SV .

        SV*     SvRV(SV* sv)

SvRV_set

Set the value of the RV pointer in sv to val. See "SvIV_set".

        void    SvRV_set(SV* sv, SV* val)

SvSTASH

Returns the stash of the SV .

        HV*     SvSTASH(SV* sv)

SvSTASH_set

Set the value of the STASH pointer in sv to val. See "SvIV_set".

        void    SvSTASH_set(SV* sv, HV* val)

SvTAINT

Taints an SV if tainting is enabled.

        void    SvTAINT(SV* sv)

SvTAINTED

Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.

        bool    SvTAINTED(SV* sv)

SvTAINTED_off

Untaints an SV . Be very careful with this routine, as it short-circuits some of Perl’s fundamental security features. XS module authors should not use this function unless they fully understand all the implications of unconditionally untainting the value. Untainting should be done in the standard perl fashion, via a carefully crafted regexp, rather than directly untainting variables.

        void    SvTAINTED_off(SV* sv)

SvTAINTED_on

Marks an SV as tainted if tainting is enabled.

        void    SvTAINTED_on(SV* sv)

SvTRUE

Returns a boolean indicating whether Perl would evaluate the SV as true or false. See SvOK() for a defined/undefined test. Does not handle ’get’ magic.

        bool    SvTRUE(SV* sv)

SvTYPE

Returns the type of the SV . See "svtype".

        svtype  SvTYPE(SV* sv)

SvUOK

Returns a boolean indicating whether the SV contains an unsigned integer.

        bool    SvUOK(SV* sv)

SvUPGRADE

Used to upgrade an SV to a more complex form. Uses "sv_upgrade" to perform the upgrade if necessary. See "svtype".

        void    SvUPGRADE(SV* sv, svtype type)

SvUTF8

Returns a U32 value indicating whether the SV contains UTF−8 encoded data. Call this after SvPV() in case any call to string overloading updates the internal flag.

        U32     SvUTF8(SV* sv)

SvUTF8_off

Unsets the UTF−8 status of an SV .

        void    SvUTF8_off(SV *sv)

SvUTF8_on

Turn on the UTF−8 status of an SV (the data is not changed, just the flag). Do not use frivolously.

        void    SvUTF8_on(SV *sv)

SvUV

Coerces the given SV to an unsigned integer and returns it. See "SvUVx" for a version which guarantees to evaluate sv only once.

        UV      SvUV(SV* sv)

SvUVX

Returns the raw value in the SV ’s UV slot, without checks or conversions. Only use when you are sure SvIOK is true. See also "SvUV()".

        UV      SvUVX(SV* sv)

SvUVx

Coerces the given SV to an unsigned integer and returns it. Guarantees to "sv" only once. Only use this if "sv" is an expression with side effects, otherwise use the more efficient "SvUV".

        UV      SvUVx(SV* sv)

SvUV_nomg

Like "SvUV" but doesn’t process magic.

        UV      SvUV_nomg(SV* sv)

SvUV_set

Set the value of the UV pointer in sv to val. See "SvIV_set".

        void    SvUV_set(SV* sv, UV val)

SvVOK

Returns a boolean indicating whether the SV contains a v−string.

        bool    SvVOK(SV* sv)

sv_catpvn_nomg

Like "sv_catpvn" but doesn’t process magic.

        void    sv_catpvn_nomg(SV* sv, const char* ptr, STRLEN len)

sv_catsv_nomg

Like "sv_catsv" but doesn’t process magic.

        void    sv_catsv_nomg(SV* dsv, SV* ssv)

sv_derived_from

Returns a boolean indicating whether the SV is derived from the specified class at the C level. To check derivation at the Perl level, call "isa()" as a normal Perl method.

        bool    sv_derived_from(SV* sv, const char* name)

sv_does

Returns a boolean indicating whether the SV performs a specific, named role. The SV can be a Perl object or the name of a Perl class.

        bool    sv_does(SV* sv, const char* name)

sv_report_used

Dump the contents of all SVs not yet freed. (Debugging aid).

        void    sv_report_used()

sv_setsv_nomg

Like "sv_setsv" but doesn’t process magic.

        void    sv_setsv_nomg(SV* dsv, SV* ssv)

sv_utf8_upgrade_nomg

Like sv_utf8_upgrade, but doesn’t do magic on "sv"

        STRLEN  sv_utf8_upgrade_nomg(NN SV *sv)

looks_like_number

Test if the content of an SV looks like a number (or is a number). "Inf" and "Infinity" are treated as numbers (so will not issue a non-numeric warning), even if your atof() doesn’t grok them.

        I32     looks_like_number(SV* sv)

newRV_noinc

Creates an RV wrapper for an SV . The reference count for the original SV is not incremented.

        SV*     newRV_noinc(SV* sv)

newSV

Creates a new SV . A non-zero "len" parameter indicates the number of bytes of preallocated string space the SV should have. An extra byte for a trailing NUL is also reserved. (SvPOK is not set for the SV even if string space is allocated.) The reference count for the new SV is set to 1.

In 5.9.3, newSV() replaces the older NEWSV () API , and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG (see " PERL_MEM_LOG " in perlhack). The older API is still there for use in XS modules supporting older perls.

        SV*     newSV(STRLEN len)

newSVhek

Creates a new SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV if the hek is NULL .

        SV*     newSVhek(const HEK *hek)

newSViv

Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.

        SV*     newSViv(IV i)

newSVnv

Creates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.

        SV*     newSVnv(NV n)

newSVpv

Creates a new SV and copies a string into it. The reference count for the SV is set to 1. If "len" is zero, Perl will compute the length using strlen(). For efficiency, consider using "newSVpvn" instead.

        SV*     newSVpv(const char* s, STRLEN len)

newSVpvf

Creates a new SV and initializes it with the string formatted like "sprintf".

        SV*     newSVpvf(const char* pat, ...)

newSVpvn

Creates a new SV and copies a string into it. The reference count for the SV is set to 1. Note that if "len" is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at least "len" bytes long. If the "s" argument is NULL the new SV will be undefined.

        SV*     newSVpvn(const char* s, STRLEN len)

newSVpvn_flags

Creates a new SV and copies a string into it. The reference count for the SV is set to 1. Note that if "len" is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at least "len" bytes long. If the "s" argument is NULL the new SV will be undefined. Currently the only flag bits accepted are "SVf_UTF8" and "SVs_TEMP". If "SVs_TEMP" is set, then "sv2mortal()" is called on the result before returning. If "SVf_UTF8" is set, then it will be set on the new SV . "newSVpvn_utf8()" is a convenience wrapper for this function, defined as

    #define newSVpvn_utf8(s, len, u)                    \
        newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)

        SV*     newSVpvn_flags(const char* s, STRLEN len, U32 flags)

newSVpvn_share

Creates a new SV with its SvPVX_const pointing to a shared string in the string table. If the string does not already exist in the table, it is created first. Turns on READONLY and FAKE . If the "hash" parameter is non-zero, that value is used; otherwise the hash is computed. The string’s hash can be later be retrieved from the SV with the "SvSHARED_HASH()" macro. The idea here is that as the string table is used for shared hash keys these strings will have SvPVX_const == HeKEY and hash lookup will avoid string compare.

        SV*     newSVpvn_share(const char* s, I32 len, U32 hash)

newSVpvs

Like "newSVpvn", but takes a literal string instead of a string/length pair.

        SV*     newSVpvs(const char* s)

newSVpvs_flags

Like "newSVpvn_flags", but takes a literal string instead of a string/length pair.

        SV*     newSVpvs_flags(const char* s, U32 flags)

newSVpvs_share

Like "newSVpvn_share", but takes a literal string instead of a string/length pair and omits the hash parameter.

        SV*     newSVpvs_share(const char* s)

newSVrv

Creates a new SV for the RV , "rv", to point to. If "rv" is not an RV then it will be upgraded to one. If "classname" is non-null then the new SV will be blessed in the specified package. The new SV is returned and its reference count is 1.

        SV*     newSVrv(SV* rv, const char* classname)

newSVsv

Creates a new SV which is an exact duplicate of the original SV . (Uses "sv_setsv").

        SV*     newSVsv(SV* old)

newSVuv

Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.

        SV*     newSVuv(UV u)

newSV_type

Creates a new SV , of the type specified. The reference count for the new SV is set to 1.

        SV*     newSV_type(svtype type)

sv_2bool

This function is only called on magical items, and is only used by sv_true() or its macro equivalent.

        bool    sv_2bool(SV* sv)

sv_2cv

Using various gambits, try to get a CV from an SV ; in addition, try if possible to set *st and *gvp to the stash and GV associated with it. The flags in "lref" are passed to sv_fetchsv.

        CV*     sv_2cv(SV* sv, HV** st, GV** gvp, I32 lref)

sv_2io

Using various gambits, try to get an IO from an SV: the IO slot if its a GV ; or the recursive result if we’re an RV ; or the IO slot of the symbol named after the PV if we’re a string.

        IO*     sv_2io(SV* sv)

sv_2iv_flags

Return the integer value of an SV , doing any necessary string conversion. If flags includes SV_GMAGIC , does an mg_get() first. Normally used via the "SvIV(sv)" and "SvIVx(sv)" macros.

        IV      sv_2iv_flags(SV* sv, I32 flags)

sv_2mortal

Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call to FREETMPS , or by an implicit call at places such as statement boundaries. SvTEMP() is turned on which means that the SV ’s string buffer can be "stolen" if this SV is copied. See also "sv_newmortal" and "sv_mortalcopy".

        SV*     sv_2mortal(SV* sv)

sv_2nv

Return the num value of an SV , doing any necessary string or integer conversion, magic etc. Normally used via the "SvNV(sv)" and "SvNVx(sv)" macros.

        NV      sv_2nv(SV* sv)

sv_2pvbyte

Return a pointer to the byte-encoded representation of the SV , and set *lp to its length. May cause the SV to be downgraded from UTF−8 as a side-effect.

Usually accessed via the "SvPVbyte" macro.

        char*   sv_2pvbyte(SV* sv, STRLEN* lp)

sv_2pvutf8

Return a pointer to the UTF−8−encoded representation of the SV , and set *lp to its length. May cause the SV to be upgraded to UTF−8 as a side-effect.

Usually accessed via the "SvPVutf8" macro.

        char*   sv_2pvutf8(SV* sv, STRLEN* lp)

sv_2pv_flags

Returns a pointer to the string value of an SV , and sets *lp to its length. If flags includes SV_GMAGIC , does an mg_get() first. Coerces sv to a string if necessary. Normally invoked via the "SvPV_flags" macro. "sv_2pv()" and "sv_2pv_nomg" usually end up here too.

        char*   sv_2pv_flags(SV* sv, STRLEN* lp, I32 flags)

sv_2uv_flags

Return the unsigned integer value of an SV , doing any necessary string conversion. If flags includes SV_GMAGIC , does an mg_get() first. Normally used via the "SvUV(sv)" and "SvUVx(sv)" macros.

        UV      sv_2uv_flags(SV* sv, I32 flags)

sv_backoff

Remove any string offset. You should normally use the "SvOOK_off" macro wrapper instead.

        int     sv_backoff(SV* sv)

sv_bless

Blesses an SV into a specified package. The SV must be an RV . The package must be designated by its stash (see "gv_stashpv()"). The reference count of the SV is unaffected.

        SV*     sv_bless(SV* sv, HV* stash)

sv_catpv

Concatenates the string onto the end of the string which is in the SV . If the SV has the UTF−8 status set, then the bytes appended should be valid UTF−8 . Handles ’get’ magic, but not ’set’ magic. See "sv_catpv_mg".

        void    sv_catpv(SV* sv, const char* ptr)

sv_catpvf

Processes its arguments like "sprintf" and appends the formatted output to an SV . If the appended data contains "wide" characters (including, but not limited to, SVs with a UTF−8 PV formatted with %s, and characters >255 formatted with %c), the original SV might get upgraded to UTF−8 . Handles ’get’ magic, but not ’set’ magic. See "sv_catpvf_mg". If the original SV was UTF−8 , the pattern should be valid UTF−8 ; if the original SV was bytes, the pattern should be too.

        void    sv_catpvf(SV* sv, const char* pat, ...)

sv_catpvf_mg

Like "sv_catpvf", but also handles ’set’ magic.

        void    sv_catpvf_mg(SV *sv, const char* pat, ...)

sv_catpvn

Concatenates the string onto the end of the string which is in the SV . The "len" indicates number of bytes to copy. If the SV has the UTF−8 status set, then the bytes appended should be valid UTF−8 . Handles ’get’ magic, but not ’set’ magic. See "sv_catpvn_mg".

        void    sv_catpvn(SV *dsv, const char *sstr, STRLEN len)

sv_catpvn_flags

Concatenates the string onto the end of the string which is in the SV . The "len" indicates number of bytes to copy. If the SV has the UTF−8 status set, then the bytes appended should be valid UTF−8 . If "flags" has "SV_GMAGIC" bit set, will "mg_get" on "dsv" if appropriate, else not. "sv_catpvn" and "sv_catpvn_nomg" are implemented in terms of this function.

        void    sv_catpvn_flags(SV *dstr, const char *sstr, STRLEN len, I32 flags)

sv_catpvs

Like "sv_catpvn", but takes a literal string instead of a string/length pair.

        void    sv_catpvs(SV* sv, const char* s)

sv_catpv_mg

Like "sv_catpv", but also handles ’set’ magic.

        void    sv_catpv_mg(SV *sv, const char *ptr)

sv_catsv

Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". Modifies "dsv" but not "ssv". Handles ’get’ magic, but not ’set’ magic. See "sv_catsv_mg".

        void    sv_catsv(SV *dstr, SV *sstr)

sv_catsv_flags

Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". Modifies "dsv" but not "ssv". If "flags" has "SV_GMAGIC" bit set, will "mg_get" on the SVs if appropriate, else not. "sv_catsv" and "sv_catsv_nomg" are implemented in terms of this function.

        void    sv_catsv_flags(SV* dsv, SV* ssv, I32 flags)

sv_chop

Efficient removal of characters from the beginning of the string buffer. SvPOK(sv) must be true and the "ptr" must be a pointer to somewhere inside the string buffer. The "ptr" becomes the first character of the adjusted string. Uses the " OOK hack". Beware: after this function returns, "ptr" and SvPVX_const(sv) may no longer refer to the same chunk of data.

        void    sv_chop(SV* sv, const char* ptr)

sv_clear

Clear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV ’s head is not freed, although its type is set to all 1’s so that it won’t inadvertently be assumed to be live during global destruction etc. This function should only be called when REFCNT is zero. Most of the time you’ll want to call "sv_free()" (or its macro wrapper "SvREFCNT_dec") instead.

        void    sv_clear(SV* sv)

sv_cmp

Compares the strings in two SVs. Returns −1, 0, or 1 indicating whether the string in "sv1" is less than, equal to, or greater than the string in "sv2". Is UTF−8 and ’use bytes’ aware, handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp_locale".

        I32     sv_cmp(SV* sv1, SV* sv2)

sv_cmp_locale

Compares the strings in two SVs in a locale-aware manner. Is UTF−8 and ’use bytes’ aware, handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp".

        I32     sv_cmp_locale(SV* sv1, SV* sv2)

sv_collxfrm

Add Collate Transform magic to an SV if it doesn’t already have it.

Any scalar variable may carry PERL_MAGIC_collxfrm magic that contains the scalar data of the variable, but transformed to such a format that a normal memory comparison can be used to compare the data according to the locale settings.

        char*   sv_collxfrm(SV* sv, STRLEN* nxp)

sv_copypv

Copies a stringified representation of the source SV into the destination SV . Automatically performs any necessary mg_get and coercion of numeric values into strings. Guaranteed to preserve UTF8 flag even from overloaded objects. Similar in nature to sv_2pv[_flags] but operates directly on an SV instead of just the string. Mostly uses sv_2pv_flags to do its work, except when that would lose the UTF−8 ’ness of the PV .

        void    sv_copypv(SV* dsv, SV* ssv)

sv_dec

Auto-decrement of the value in the SV , doing string to numeric conversion if necessary. Handles ’get’ magic.

        void    sv_dec(SV* sv)

sv_eq

Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF−8 and ’use bytes’ aware, handles get magic, and will coerce its args to strings if necessary.

        I32     sv_eq(SV* sv1, SV* sv2)

sv_force_normal_flags

Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we’re a ref, stop refing; if we’re a glob, downgrade to an xpvmg; if we’re a copy-on-write scalar, this is the on-write time when we do the copy, and is also used locally. If "SV_COW_DROP_PV" is set then a copy-on-write scalar drops its PV buffer (if any) and becomes SvPOK_off rather than making a copy. (Used where this scalar is about to be set to some other value.) In addition, the "flags" parameter gets passed to "sv_unref_flags()" when unrefing. "sv_force_normal" calls this function with flags set to 0.

        void    sv_force_normal_flags(SV *sv, U32 flags)

sv_free

Decrement an SV ’s reference count, and if it drops to zero, call "sv_clear" to invoke destructors and free up any memory used by the body; finally, deallocate the SV ’s head itself. Normally called via a wrapper macro "SvREFCNT_dec".

        void    sv_free(SV* sv)

sv_gets

Get a line from the filehandle and store it into the SV , optionally appending to the currently-stored string.

        char*   sv_gets(SV* sv, PerlIO* fp, I32 append)

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* sv, STRLEN newlen)

sv_inc

Auto-increment of the value in the SV , doing string to numeric conversion if necessary. Handles ’get’ magic.

        void    sv_inc(SV* sv)

sv_insert

Inserts a string at the specified offset/length within the SV . Similar to the Perl substr() function. Handles get magic.

        void    sv_insert(SV *bigstr, STRLEN offset, STRLEN len, const char *little, STRLEN littlelen)

sv_insert_flags

Same as "sv_insert", but the extra "flags" are passed the "SvPV_force_flags" that applies to "bigstr".

        void    sv_insert_flags(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen, const U32 flags)

sv_isa

Returns a boolean indicating whether the SV is blessed into the specified class. This does not check for subtypes; use "sv_derived_from" to verify an inheritance relationship.

        int     sv_isa(SV* sv, const char* name)

sv_isobject

Returns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is not an RV , or if the object is not blessed, then this will return false.

        int     sv_isobject(SV* sv)