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perlapi (1)

Name

perlapi - autogenerated documentation for the perl public API

Synopsis

Please see following description for synopsis

Description




Perl Programmers Reference Guide                       PERLAPI(1)



NAME
     perlapi - autogenerated documentation for the perl public
     API

DESCRIPTION
     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" Values
     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



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     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.

Array Manipulation Functions
     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



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             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.



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             "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(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)




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     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)

Callback Functions
     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)




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     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;




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

                             SAVETMPS;

Character classes
     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)

Cloning an interpreter
     perl_clone



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             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)

CV Manipulation Functions
     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



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             "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)

Embedding Functions
     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



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             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)

Functions in file dump.c
     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



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             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



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             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)

Functions in file mathoms.c
     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



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             "SvPV_nolen(sv)" instead.
                  char*     sv_2pv_nolen(SV* sv)

     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)



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     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.
                  void sv_taint(SV* sv)

     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".



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                     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)

Functions in file perl.h
     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()

Functions in file pp_ctl.c
     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



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             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)

Functions in file pp_pack.c
     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)

Functions in file pp_sys.c
     setdefout
             Sets PL_defoutgv, the default file handle for
             output, to the passed in typeglob. As PL_defoutgv
             "owns" a reference on its typeglob, the reference
             count of the passed in typeglob is increased by one,
             and the reference count of the typeglob that
             PL_defoutgv points to is decreased by one.

                     void    setdefout(GV* gv)

Global Variables
     PL_keyword_plugin
             Function pointer, pointing at a function used to
             handle extended keywords.  The function should be
             declared as

                     int keyword_plugin_function(pTHX_
                             char *keyword_ptr, STRLEN keyword_len,
                             OP **op_ptr)

             The function is called from the tokeniser, whenever
             a possible keyword is seen.  "keyword_ptr" points at
             the word in the parser's input buffer, and
             "keyword_len" gives its length; it is not null-
             terminated.  The function is expected to examine the
             word, and possibly other state such as %^H, to
             decide whether it wants to handle it as an extended
             keyword.  If it does not, the function should return
             "KEYWORD_PLUGIN_DECLINE", and the normal parser
             process will continue.



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             If the function wants to handle the keyword, it
             first must parse anything following the keyword that
             is part of the syntax introduced by the keyword.
             See "Lexer interface" for details.

             When a keyword is being handled, the plugin function
             must build a tree of "OP" structures, representing
             the code that was parsed.  The root of the tree must
             be stored in *op_ptr.  The function then returns a
             contant indicating the syntactic role of the
             construct that it has parsed: "KEYWORD_PLUGIN_STMT"
             if it is a complete statement, or
             "KEYWORD_PLUGIN_EXPR" if it is an expression.  Note
             that a statement construct cannot be used inside an
             expression (except via "do BLOCK" and similar), and
             an expression is not a complete statement (it
             requires at least a terminating semicolon).

             When a keyword is handled, the plugin function may
             also have (compile-time) side effects.  It may
             modify "%^H", define functions, and so on.
             Typically, if side effects are the main purpose of a
             handler, it does not wish to generate any ops to be
             included in the normal compilation.  In this case it
             is still required to supply an op tree, but it
             suffices to generate a single null op.

             That's how the *PL_keyword_plugin function needs to
             behave overall.  Conventionally, however, one does
             not completely replace the existing handler
             function.  Instead, take a copy of
             "PL_keyword_plugin" before assigning your own
             function pointer to it.  Your handler function
             should look for keywords that it is interested in
             and handle those.  Where it is not interested, it
             should call the saved plugin function, passing on
             the arguments it received.  Thus "PL_keyword_plugin"
             actually points at a chain of handler functions, all
             of which have an opportunity to handle keywords, and
             only the last function in the chain (built into the
             Perl core) will normally return
             "KEYWORD_PLUGIN_DECLINE".

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

GV Functions
     GvSV    Return the SV from the GV.

                     SV*     GvSV(GV* gv)

     gv_const_sv



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             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.



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             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)

Handy Values
     Nullav  Null AV pointer.



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             (deprecated - use "(AV *)NULL" instead)

     Nullch  Null character pointer. (No longer available when
             "PERL_CORE" is defined.)

     Nullcv  Null CV pointer.

             (deprecated - use "(CV *)NULL" instead)

     Nullhv  Null HV pointer.

             (deprecated - use "(HV *)NULL" instead)

     Nullsv  Null SV pointer. (No longer available when
             "PERL_CORE" is defined.)

Hash Manipulation Functions
     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.




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                     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)




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     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.



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                     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)



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     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



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             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



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             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



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             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()

Lexer interface
     lex_bufutf8
             Indicates whether the octets in the lexer buffer
             ("PL_parser->linestr") should be interpreted as the
             UTF-8 encoding of Unicode characters.  If not, they
             should be interpreted as Latin-1 characters.  This
             is analogous to the "SvUTF8" flag for scalars.

             In UTF-8 mode, it is not guaranteed that the lexer
             buffer actually contains valid UTF-8.  Lexing code
             must be robust in the face of invalid encoding.

             The actual "SvUTF8" flag of the "PL_parser->linestr"
             scalar is significant, but not the whole story
             regarding the input character encoding.  Normally,
             when a file is being read, the scalar contains
             octets and its "SvUTF8" flag is off, but the octets
             should be interpreted as UTF-8 if the "use utf8"
             pragma is in effect.  During a string eval, however,
             the scalar may have the "SvUTF8" flag on, and in
             this case its octets should be interpreted as UTF-8
             unless the "use bytes" pragma is in effect.  This
             logic may change in the future; use this function
             instead of implementing the logic yourself.

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

                     bool    lex_bufutf8()

     lex_discard_to
             Discards the first part of the "PL_parser->linestr"
             buffer, up to ptr.  The remaining content of the
             buffer will be moved, and all pointers into the
             buffer updated appropriately.  ptr must not be later
             in the buffer than the position of
             "PL_parser->bufptr": it is not permitted to discard
             text that has yet to be lexed.




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             Normally it is not necessarily to do this directly,
             because it suffices to use the implicit discarding
             behaviour of "lex_next_chunk" and things based on
             it.  However, if a token stretches across multiple
             lines, and the lexing code has kept multiple lines
             of text in the buffer fof that purpose, then after
             completion of the token it would be wise to
             explicitly discard the now-unneeded earlier lines,
             to avoid future multi-line tokens growing the buffer
             without bound.

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

                     void    lex_discard_to(char *ptr)

     lex_grow_linestr
             Reallocates the lexer buffer ("PL_parser->linestr")
             to accommodate at least len octets (including
             terminating NUL).  Returns a pointer to the
             reallocated buffer.  This is necessary before making
             any direct modification of the buffer that would
             increase its length.  "lex_stuff_pvn" provides a
             more convenient way to insert text into the buffer.

             Do not use "SvGROW" or "sv_grow" directly on
             "PL_parser->linestr"; this function updates all of
             the lexer's variables that point directly into the
             buffer.

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

                     char *  lex_grow_linestr(STRLEN len)

     lex_next_chunk
             Reads in the next chunk of text to be lexed,
             appending it to "PL_parser->linestr".  This should
             be called when lexing code has looked to the end of
             the current chunk and wants to know more.  It is
             usual, but not necessary, for lexing to have
             consumed the entirety of the current chunk at this
             time.

             If "PL_parser->bufptr" is pointing to the very end
             of the current chunk (i.e., the current chunk has
             been entirely consumed), normally the current chunk
             will be discarded at the same time that the new
             chunk is read in.  If flags includes
             "LEX_KEEP_PREVIOUS", the current chunk will not be
             discarded.  If the current chunk has not been
             entirely consumed, then it will not be discarded



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             regardless of the flag.

             Returns true if some new text was added to the
             buffer, or false if the buffer has reached the end
             of the input text.

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

                     bool    lex_next_chunk(U32 flags)

     lex_peek_unichar
             Looks ahead one (Unicode) character in the text
             currently being lexed.  Returns the codepoint
             (unsigned integer value) of the next character, or
             -1 if lexing has reached the end of the input text.
             To consume the peeked character, use
             "lex_read_unichar".

             If the next character is in (or extends into) the
             next chunk of input text, the next chunk will be
             read in.  Normally the current chunk will be
             discarded at the same time, but if flags includes
             "LEX_KEEP_PREVIOUS" then the current chunk will not
             be discarded.

             If the input is being interpreted as UTF-8 and a
             UTF-8 encoding error is encountered, an exception is
             generated.

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

                     I32     lex_peek_unichar(U32 flags)

     lex_read_space
             Reads optional spaces, in Perl style, in the text
             currently being lexed.  The spaces may include
             ordinary whitespace characters and Perl-style
             comments.  "#line" directives are processed if
             encountered.  "PL_parser->bufptr" is moved past the
             spaces, so that it points at a non-space character
             (or the end of the input text).

             If spaces extend into the next chunk of input text,
             the next chunk will be read in.  Normally the
             current chunk will be discarded at the same time,
             but if flags includes "LEX_KEEP_PREVIOUS" then the
             current chunk will not be discarded.

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



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                     void    lex_read_space(U32 flags)

     lex_read_to
             Consume text in the lexer buffer, from
             "PL_parser->bufptr" up to ptr.  This advances
             "PL_parser->bufptr" to match ptr, performing the
             correct bookkeeping whenever a newline character is
             passed.  This is the normal way to consume lexed
             text.

             Interpretation of the buffer's octets can be
             abstracted out by using the slightly higher-level
             functions "lex_peek_unichar" and "lex_read_unichar".

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

                     void    lex_read_to(char *ptr)

     lex_read_unichar
             Reads the next (Unicode) character in the text
             currently being lexed.  Returns the codepoint
             (unsigned integer value) of the character read, and
             moves "PL_parser->bufptr" past the character, or
             returns -1 if lexing has reached the end of the
             input text.  To non-destructively examine the next
             character, use "lex_peek_unichar" instead.

             If the next character is in (or extends into) the
             next chunk of input text, the next chunk will be
             read in.  Normally the current chunk will be
             discarded at the same time, but if flags includes
             "LEX_KEEP_PREVIOUS" then the current chunk will not
             be discarded.

             If the input is being interpreted as UTF-8 and a
             UTF-8 encoding error is encountered, an exception is
             generated.

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

                     I32     lex_read_unichar(U32 flags)

     lex_stuff_pvn
             Insert characters into the lexer buffer
             ("PL_parser->linestr"), immediately after the
             current lexing point ("PL_parser->bufptr"),
             reallocating the buffer if necessary.  This means
             that lexing code that runs later will see the
             characters as if they had appeared in the input.  It
             is not recommended to do this as part of normal



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             parsing, and most uses of this facility run the risk
             of the inserted characters being interpreted in an
             unintended manner.

             The string to be inserted is represented by len
             octets starting at pv.  These octets are interpreted
             as either UTF-8 or Latin-1, according to whether the
             "LEX_STUFF_UTF8" flag is set in flags.  The
             characters are recoded for the lexer buffer,
             according to how the buffer is currently being
             interpreted ("lex_bufutf8").  If a string to be
             interpreted is available as a Perl scalar, the
             "lex_stuff_sv" function is more convenient.

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

                     void    lex_stuff_pvn(char *pv, STRLEN len, U32 flags)

     lex_stuff_sv
             Insert characters into the lexer buffer
             ("PL_parser->linestr"), immediately after the
             current lexing point ("PL_parser->bufptr"),
             reallocating the buffer if necessary.  This means
             that lexing code that runs later will see the
             characters as if they had appeared in the input.  It
             is not recommended to do this as part of normal
             parsing, and most uses of this facility run the risk
             of the inserted characters being interpreted in an
             unintended manner.

             The string to be inserted is the string value of sv.
             The characters are recoded for the lexer buffer,
             according to how the buffer is currently being
             interpreted ("lex_bufutf8").  If a string to be
             interpreted is not already a Perl scalar, the
             "lex_stuff_pvn" function avoids the need to
             construct a scalar.

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

                     void    lex_stuff_sv(SV *sv, U32 flags)

     lex_unstuff
             Discards text about to be lexed, from
             "PL_parser->bufptr" up to ptr.  Text following ptr
             will be moved, and the buffer shortened.  This hides
             the discarded text from any lexing code that runs
             later, as if the text had never appeared.

             This is not the normal way to consume lexed text.



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             For that, use "lex_read_to".

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

                     void    lex_unstuff(char *ptr)

     PL_parser
             Pointer to a structure encapsulating the state of
             the parsing operation currently in progress.  The
             pointer can be locally changed to perform a nested
             parse without interfering with the state of an outer
             parse.  Individual members of "PL_parser" have their
             own documentation.

     PL_parser->bufend
             Direct pointer to the end of the chunk of text
             currently being lexed, the end of the lexer buffer.
             This is equal to "SvPVX(PL_parser->linestr) +
             SvCUR(PL_parser->linestr)".  A NUL character (zero
             octet) is always located at the end of the buffer,
             and does not count as part of the buffer's contents.

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

     PL_parser->bufptr
             Points to the current position of lexing inside the
             lexer buffer.  Characters around this point may be
             freely examined, within the range delimited by
             "SvPVX("PL_parser->linestr")" and
             "PL_parser->bufend".  The octets of the buffer may
             be intended to be interpreted as either UTF-8 or
             Latin-1, as indicated by "lex_bufutf8".

             Lexing code (whether in the Perl core or not) moves
             this pointer past the characters that it consumes.
             It is also expected to perform some bookkeeping
             whenever a newline character is consumed.  This
             movement can be more conveniently performed by the
             function "lex_read_to", which handles newlines
             appropriately.

             Interpretation of the buffer's octets can be
             abstracted out by using the slightly higher-level
             functions "lex_peek_unichar" and "lex_read_unichar".

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

     PL_parser->linestart
             Points to the start of the current line inside the



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             lexer buffer.  This is useful for indicating at
             which column an error occurred, and not much else.
             This must be updated by any lexing code that
             consumes a newline; the function "lex_read_to"
             handles this detail.

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

     PL_parser->linestr
             Buffer scalar containing the chunk currently under
             consideration of the text currently being lexed.
             This is always a plain string scalar (for which
             "SvPOK" is true).  It is not intended to be used as
             a scalar by normal scalar means; instead refer to
             the buffer directly by the pointer variables
             described below.

             The lexer maintains various "char*" pointers to
             things in the "PL_parser->linestr" buffer.  If
             "PL_parser->linestr" is ever reallocated, all of
             these pointers must be updated.  Don't attempt to do
             this manually, but rather use "lex_grow_linestr" if
             you need to reallocate the buffer.

             The content of the text chunk in the buffer is
             commonly exactly one complete line of input, up to
             and including a newline terminator, but there are
             situations where it is otherwise.  The octets of the
             buffer may be intended to be interpreted as either
             UTF-8 or Latin-1.  The function "lex_bufutf8" tells
             you which.  Do not use the "SvUTF8" flag on this
             scalar, which may disagree with it.

             For direct examination of the buffer, the variable
             "PL_parser->bufend" points to the end of the buffer.
             The current lexing position is pointed to by
             "PL_parser->bufptr".  Direct use of these pointers
             is usually preferable to examination of the scalar
             through normal scalar means.

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

Magical Functions
     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



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             "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)




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     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)

Memory Management
     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



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             "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



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             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



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             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)

Miscellaneous Functions
     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.




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                 (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:




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                 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)

     prescan_version
                     const char*     prescan_version(const char *s, bool strict, const char** errstr, bool *sqv, int *ssaw_decimal, int *swidth, bool *salpha)

     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.




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                     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);




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             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)





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MRO Functions
     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)

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

                             dMULTICALL;

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




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                             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;

Numeric functions
     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.



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             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).




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                     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



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             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)

Optree Manipulation Functions
     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(const CV *const cv)

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

             Passing NULL for SV creates a constant sub
             equivalent to "sub BAR () {}", which won't be called
             if used as a destructor, but will suppress the
             overhead of a call to "AUTOLOAD".  (This form,
             however, isn't 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.





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Pad Data Structures
     pad_findmy
             Given a lexical name, try to find its offset, first
             in the current pad, or failing that, in the pads of
             any lexically enclosing subs (including the
             complications introduced by eval). If the name is
             found in an outer pad, then a fake entry is added to
             the current pad.  Returns the offset in the current
             pad, or NOT_IN_PAD on failure.

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

                     PADOFFSET       pad_findmy(const char* name, STRLEN len, U32 flags)

     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)

Per-Interpreter Variables
     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_opfreehook
             When non-"NULL", the function pointed by this
             variable will be called each time an OP is freed
             with the corresponding OP as the argument.  This
             allows extensions to free any extra attribute they
             have locally attached to an OP.  It is also assured
             to first fire for the parent OP and then for its
             kids.

             When you replace this variable, it is considered a
             good practice to store the possibly previously



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             installed hook and that you recall it inside your
             own.

                     Perl_ophook_t   PL_opfreehook

     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

REGEXP Functions
     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)

Simple Exception Handling Macros
     dXCPT   Set up necessary local variables for exception



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             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.

Stack Manipulation Macros
     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".




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                     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)




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     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



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             "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;



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     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



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             "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".




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                     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)

SV Flags
     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".



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     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".

SV Manipulation Functions
     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".



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                     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)




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     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)



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     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



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             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



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             "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 pointer to the
             string buffer is offset.  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 actually
             "SvOOK_offset()" bytes before SvPVX.  This offset
             used to be stored in SvIVX, but is now stored within
             the spare part of the buffer.

                     U32     SvOOK(SV* sv)

     SvOOK_offset
             Reads into len the offset from SvPVX back to the
             true start of the allocated buffer, which will be
             non-zero if "sv_chop" has been used to efficiently
             remove characters from start of the buffer.
             Implemented as a macro, which takes the address of
             len, which must be of type "STRLEN".  Evaluates sv
             more than once. Sets len to 0 if "SvOOK(sv)" is
             false.

                     void    SvOOK_offset(NN SV*sv, STRLEN len)

     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)



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     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.



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                     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)



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     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)



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     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.



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                     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.




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                     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()".



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                     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 *const 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 *const name)

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



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                     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)

SV-Body Allocation
     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 *const sv)

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

                     SV*     newRV_noinc(SV *const 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(const 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 *const hek)




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

                     SV*     newSViv(const 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(const 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 *const s, const STRLEN len)

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

                     SV*     newSVpvf(const char *const 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 *const s, const 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, "s" is considered
             to be in UTF-8 and the "SVf_UTF8" flag 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)




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                     SV*     newSVpvn_flags(const char *const s, const STRLEN len, const 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 *const rv, const char *const classname)

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

                     SV*     newSVsv(SV *const old)

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




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                     SV*     newSVuv(const 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(const 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 *const 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 gv_fetchsv.

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



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     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 *const sv, STRLEN *const 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 *const sv, STRLEN *const 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 *const sv, STRLEN *const lp, const 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 *const sv, const I32 flags)

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

                     int     sv_backoff(SV *const 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 *const sv, HV *const stash)

     sv_catpv
             Concatenates the string onto the end of the string



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             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 *const 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 *const sv, const char *const pat, ...)

     sv_catpvf_mg
             Like "sv_catpvf", but also handles 'set' magic.

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

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




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

     sv_catpv_mg
             Like "sv_catpv", but also handles 'set' magic.

                     void    sv_catpv_mg(SV *const sv, const char *const 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 *const dsv, SV *const ssv, const 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 *const sv, const char *const 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 *const 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,



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             and will coerce its args to strings if necessary.
             See also "sv_cmp_locale".

                     I32     sv_cmp(SV *const sv1, SV *const 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 *const sv1, SV *const 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 *const sv, STRLEN *const 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 *const dsv, SV *const 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 *const 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



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             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 *const sv, const 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 *const 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 *const sv, PerlIO *const 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 *const 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 *const 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 *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen)

     sv_insert_flags
             Same as "sv_insert", but the extra "flags" are



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             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 *const 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)

     sv_len  Returns the length of the string in the SV. Handles
             magic and type coercion.  See also "SvCUR", which
             gives raw access to the xpv_cur slot.

                     STRLEN  sv_len(SV *const sv)

     sv_len_utf8
             Returns the number of characters in the string in an
             SV, counting wide UTF-8 bytes as a single character.
             Handles magic and type coercion.

                     STRLEN  sv_len_utf8(SV *const sv)

     sv_magic
             Adds magic to an SV. First upgrades "sv" to type
             "SVt_PVMG" if necessary, then adds a new magic item
             of type "how" to the head of the magic list.

             See "sv_magicext" (which "sv_magic" now calls) for a
             description of the handling of the "name" and
             "namlen" arguments.

             You need to use "sv_magicext" to add magic to
             SvREADONLY SVs and also to add more than one
             instance of the same 'how'.

                     void    sv_magic(SV *const sv, SV *const obj, const int how, const char *const name, const I32 namlen)

     sv_magicext
             Adds magic to an SV, upgrading it if necessary.
             Applies the supplied vtable and returns a pointer to
             the magic added.



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             Note that "sv_magicext" will allow things that
             "sv_magic" will not.  In particular, you can add
             magic to SvREADONLY SVs, and add more than one
             instance of the same 'how'.

             If "namlen" is greater than zero then a "savepvn"
             copy of "name" is stored, if "namlen" is zero then
             "name" is stored as-is and - as another special case
             - if "(name && namlen == HEf_SVKEY)" then "name" is
             assumed to contain an "SV*" and is stored as-is with
             its REFCNT incremented.

             (This is now used as a subroutine by "sv_magic".)

                     MAGIC * sv_magicext(SV *const sv, SV *const obj, const int how, const MGVTBL *const vtbl, const char *const name, const I32 namlen)

     sv_mortalcopy
             Creates a new SV which is a copy of the original SV
             (using "sv_setsv").  The new SV is marked as mortal.
             It will be destroyed "soon", either by an explicit
             call to FREETMPS, or by an implicit call at places
             such as statement boundaries.  See also
             "sv_newmortal" and "sv_2mortal".

                     SV*     sv_mortalcopy(SV *const oldsv)

     sv_newmortal
             Creates a new null SV which is mortal.  The
             reference count of the SV is set to 1. It will be
             destroyed "soon", either by an explicit call to
             FREETMPS, or by an implicit call at places such as
             statement boundaries.  See also "sv_mortalcopy" and
             "sv_2mortal".

                     SV*     sv_newmortal()

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

                     SV*     sv_newref(SV *const sv)

     sv_pos_b2u
             Converts the value pointed to by offsetp from a
             count of bytes from the start of the string, to a
             count of the equivalent number of UTF-8 chars.
             Handles magic and type coercion.

                     void    sv_pos_b2u(SV *const sv, I32 *const offsetp)

     sv_pos_u2b
             Converts the value pointed to by offsetp from a



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             count of UTF-8 chars from the start of the string,
             to a count of the equivalent number of bytes; if
             lenp is non-zero, it does the same to lenp, but this
             time starting from the offset, rather than from the
             start of the string. Handles magic and type
             coercion.

             Use "sv_pos_u2b_flags" in preference, which
             correctly handles strings longer than 2Gb.

                     void    sv_pos_u2b(SV *const sv, I32 *const offsetp, I32 *const lenp)

     sv_pos_u2b_flags
             Converts the value pointed to by offsetp from a
             count of UTF-8 chars from the start of the string,
             to a count of the equivalent number of bytes; if
             lenp is non-zero, it does the same to lenp, but this
             time starting from the offset, rather than from the
             start of the string. Handles type coercion.  flags
             is passed to "SvPV_flags", and usually should be
             "SV_GMAGIC|SV_CONST_RETURN" to handle magic.

                     STRLEN  sv_pos_u2b_flags(SV *const sv, STRLEN uoffset, STRLEN *const lenp, U32 flags)

     sv_pvbyten_force
             The backend for the "SvPVbytex_force" macro. Always
             use the macro instead.

                     char*   sv_pvbyten_force(SV *const sv, STRLEN *const lp)

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

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

     sv_pvn_force_flags
             Get a sensible string out of the SV somehow.  If
             "flags" has "SV_GMAGIC" bit set, will "mg_get" on
             "sv" if appropriate, else not. "sv_pvn_force" and
             "sv_pvn_force_nomg" are implemented in terms of this
             function.  You normally want to use the various
             wrapper macros instead: see "SvPV_force" and
             "SvPV_force_nomg"

                     char*   sv_pvn_force_flags(SV *const sv, STRLEN *const lp, const I32 flags)

     sv_pvutf8n_force
             The backend for the "SvPVutf8x_force" macro. Always
             use the macro instead.



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                     char*   sv_pvutf8n_force(SV *const sv, STRLEN *const lp)

     sv_reftype
             Returns a string describing what the SV is a
             reference to.

                     const char*     sv_reftype(const SV *const sv, const int ob)

     sv_replace
             Make the first argument a copy of the second, then
             delete the original.  The target SV physically takes
             over ownership of the body of the source SV and
             inherits its flags; however, the target keeps any
             magic it owns, and any magic in the source is
             discarded.  Note that this is a rather specialist SV
             copying operation; most of the time you'll want to
             use "sv_setsv" or one of its many macro front-ends.

                     void    sv_replace(SV *const sv, SV *const nsv)

     sv_reset
             Underlying implementation for the "reset" Perl
             function.  Note that the perl-level function is
             vaguely deprecated.

                     void    sv_reset(const char* s, HV *const stash)

     sv_rvweaken
             Weaken a reference: set the "SvWEAKREF" flag on this
             RV; give the referred-to SV "PERL_MAGIC_backref"
             magic if it hasn't already; and push a back-
             reference to this RV onto the array of
             backreferences associated with that magic. If the RV
             is magical, set magic will be called after the RV is
             cleared.

                     SV*     sv_rvweaken(SV *const sv)

     sv_setiv
             Copies an integer into the given SV, upgrading first
             if necessary.  Does not handle 'set' magic.  See
             also "sv_setiv_mg".

                     void    sv_setiv(SV *const sv, const IV num)

     sv_setiv_mg
             Like "sv_setiv", but also handles 'set' magic.

                     void    sv_setiv_mg(SV *const sv, const IV i)

     sv_setnv
             Copies a double into the given SV, upgrading first



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             if necessary.  Does not handle 'set' magic.  See
             also "sv_setnv_mg".

                     void    sv_setnv(SV *const sv, const NV num)

     sv_setnv_mg
             Like "sv_setnv", but also handles 'set' magic.

                     void    sv_setnv_mg(SV *const sv, const NV num)

     sv_setpv
             Copies a string into an SV.  The string must be
             null-terminated.  Does not handle 'set' magic.  See
             "sv_setpv_mg".

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

     sv_setpvf
             Works like "sv_catpvf" but copies the text into the
             SV instead of appending it.  Does not handle 'set'
             magic.  See "sv_setpvf_mg".

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

     sv_setpvf_mg
             Like "sv_setpvf", but also handles 'set' magic.

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

     sv_setpviv
             Copies an integer into the given SV, also updating
             its string value.  Does not handle 'set' magic.  See
             "sv_setpviv_mg".

                     void    sv_setpviv(SV *const sv, const IV num)

     sv_setpviv_mg
             Like "sv_setpviv", but also handles 'set' magic.

                     void    sv_setpviv_mg(SV *const sv, const IV iv)

     sv_setpvn
             Copies a string into an SV.  The "len" parameter
             indicates the number of bytes to be copied.  If the
             "ptr" argument is NULL the SV will become undefined.
             Does not handle 'set' magic.  See "sv_setpvn_mg".

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

     sv_setpvn_mg
             Like "sv_setpvn", but also handles 'set' magic.




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

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

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

     sv_setpv_mg
             Like "sv_setpv", but also handles 'set' magic.

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

     sv_setref_iv
             Copies an integer into a new SV, optionally blessing
             the SV.  The "rv" argument will be upgraded to an
             RV.  That RV will be modified to point to the new
             SV.  The "classname" argument indicates the package
             for the blessing.  Set "classname" to "NULL" to
             avoid the blessing.  The new SV will have a
             reference count of 1, and the RV will be returned.

                     SV*     sv_setref_iv(SV *const rv, const char *const classname, const IV iv)

     sv_setref_nv
             Copies a double into a new SV, optionally blessing
             the SV.  The "rv" argument will be upgraded to an
             RV.  That RV will be modified to point to the new
             SV.  The "classname" argument indicates the package
             for the blessing.  Set "classname" to "NULL" to
             avoid the blessing.  The new SV will have a
             reference count of 1, and the RV will be returned.

                     SV*     sv_setref_nv(SV *const rv, const char *const classname, const NV nv)

     sv_setref_pv
             Copies a pointer into a new SV, optionally blessing
             the SV.  The "rv" argument will be upgraded to an
             RV.  That RV will be modified to point to the new
             SV.  If the "pv" argument is NULL then "PL_sv_undef"
             will be placed into the SV.  The "classname"
             argument indicates the package for the blessing.
             Set "classname" to "NULL" to avoid the blessing.
             The new SV will have a reference count of 1, and the
             RV will be returned.

             Do not use with other Perl types such as HV, AV, SV,
             CV, because those objects will become corrupted by
             the pointer copy process.

             Note that "sv_setref_pvn" copies the string while
             this copies the pointer.



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                     SV*     sv_setref_pv(SV *const rv, const char *const classname, void *const pv)

     sv_setref_pvn
             Copies a string into a new SV, optionally blessing
             the SV.  The length of the string must be specified
             with "n".  The "rv" argument will be upgraded to an
             RV.  That RV will be modified to point to the new
             SV.  The "classname" argument indicates the package
             for the blessing.  Set "classname" to "NULL" to
             avoid the blessing.  The new SV will have a
             reference count of 1, and the RV will be returned.

             Note that "sv_setref_pv" copies the pointer while
             this copies the string.

                     SV*     sv_setref_pvn(SV *const rv, const char *const classname, const char *const pv, const STRLEN n)

     sv_setref_uv
             Copies an unsigned integer into a new SV, optionally
             blessing the SV.  The "rv" argument will be upgraded
             to an RV.  That RV will be modified to point to the
             new SV.  The "classname" argument indicates the
             package for the blessing.  Set "classname" to "NULL"
             to avoid the blessing.  The new SV will have a
             reference count of 1, and the RV will be returned.

                     SV*     sv_setref_uv(SV *const rv, const char *const classname, const UV uv)

     sv_setsv
             Copies the contents of the source SV "ssv" into the
             destination SV "dsv".  The source SV may be
             destroyed if it is mortal, so don't use this
             function if the source SV needs to be reused. Does
             not handle 'set' magic.  Loosely speaking, it
             performs a copy-by-value, obliterating any previous
             content of the destination.

             You probably want to use one of the assortment of
             wrappers, such as "SvSetSV", "SvSetSV_nosteal",
             "SvSetMagicSV" and "SvSetMagicSV_nosteal".

                     void    sv_setsv(SV *dstr, SV *sstr)

     sv_setsv_flags
             Copies the contents of the source SV "ssv" into the
             destination SV "dsv".  The source SV may be
             destroyed if it is mortal, so don't use this
             function if the source SV needs to be reused. Does
             not handle 'set' magic.  Loosely speaking, it
             performs a copy-by-value, obliterating any previous
             content of the destination.  If the "flags"
             parameter has the "SV_GMAGIC" bit set, will "mg_get"



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             on "ssv" if appropriate, else not. If the "flags"
             parameter has the "NOSTEAL" bit set then the buffers
             of temps will not be stolen. <sv_setsv> and
             "sv_setsv_nomg" are implemented in terms of this
             function.

             You probably want to use one of the assortment of
             wrappers, such as "SvSetSV", "SvSetSV_nosteal",
             "SvSetMagicSV" and "SvSetMagicSV_nosteal".

             This is the primary function for copying scalars,
             and most other copy-ish functions and macros use
             this underneath.

                     void    sv_setsv_flags(SV *dstr, SV *sstr, const I32 flags)

     sv_setsv_mg
             Like "sv_setsv", but also handles 'set' magic.

                     void    sv_setsv_mg(SV *const dstr, SV *const sstr)

     sv_setuv
             Copies an unsigned integer into the given SV,
             upgrading first if necessary.  Does not handle 'set'
             magic.  See also "sv_setuv_mg".

                     void    sv_setuv(SV *const sv, const UV num)

     sv_setuv_mg
             Like "sv_setuv", but also handles 'set' magic.

                     void    sv_setuv_mg(SV *const sv, const UV u)

     sv_tainted
             Test an SV for taintedness. Use "SvTAINTED" instead.
                  bool sv_tainted(SV *const sv)

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

                     I32     sv_true(SV *const sv)

     sv_unmagic
             Removes all magic of type "type" from an SV.

                     int     sv_unmagic(SV *const sv, const int type)

     sv_unref_flags
             Unsets the RV status of the SV, and decrements the
             reference count of whatever was being referenced by



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             the RV.  This can almost be thought of as a reversal
             of "newSVrv".  The "cflags" argument can contain
             "SV_IMMEDIATE_UNREF" to force the reference count to
             be decremented (otherwise the decrementing is
             conditional on the reference count being different
             from one or the reference being a readonly SV).  See
             "SvROK_off".

                     void    sv_unref_flags(SV *const ref, const U32 flags)

     sv_untaint
             Untaint an SV. Use "SvTAINTED_off" instead.
                  void sv_untaint(SV *const sv)

     sv_upgrade
             Upgrade an SV to a more complex form.  Generally
             adds a new body type to the SV, then copies across
             as much information as possible from the old body.
             You generally want to use the "SvUPGRADE" macro
             wrapper. See also "svtype".

                     void    sv_upgrade(SV *const sv, svtype new_type)

     sv_usepvn_flags
             Tells an SV to use "ptr" to find its string value.
             Normally the string is stored inside the SV but
             sv_usepvn allows the SV to use an outside string.
             The "ptr" should point to memory that was allocated
             by "malloc".  The string length, "len", must be
             supplied.  By default this function will realloc
             (i.e. move) the memory pointed to by "ptr", so that
             pointer should not be freed or used by the
             programmer after giving it to sv_usepvn, and neither
             should any pointers from "behind" that pointer (e.g.
             ptr + 1) be used.

             If "flags" & SV_SMAGIC is true, will call
             SvSETMAGIC. If "flags" & SV_HAS_TRAILING_NUL is
             true, then "ptr[len]" must be NUL, and the realloc
             will be skipped. (i.e. the buffer is actually at
             least 1 byte longer than "len", and already meets
             the requirements for storing in "SvPVX")

                     void    sv_usepvn_flags(SV *const sv, char* ptr, const STRLEN len, const U32 flags)

     sv_utf8_decode
             If the PV of the SV is an octet sequence in UTF-8
             and contains a multiple-byte character, the "SvUTF8"
             flag is turned on so that it looks like a character.
             If the PV contains only single-byte characters, the
             "SvUTF8" flag stays being off.  Scans PV for
             validity and returns false if the PV is invalid



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             UTF-8.

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

                     bool    sv_utf8_decode(SV *const sv)

     sv_utf8_downgrade
             Attempts to convert the PV of an SV from characters
             to bytes.  If the PV contains a character that
             cannot fit in a byte, this conversion will fail; in
             this case, either returns false or, if "fail_ok" is
             not true, croaks.

             This is not as a general purpose Unicode to byte
             encoding interface: use the Encode extension for
             that.

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

                     bool    sv_utf8_downgrade(SV *const sv, const bool fail_ok)

     sv_utf8_encode
             Converts the PV of an SV to UTF-8, but then turns
             the "SvUTF8" flag off so that it looks like octets
             again.

                     void    sv_utf8_encode(SV *const sv)

     sv_utf8_upgrade
             Converts the PV of an SV to its UTF-8-encoded form.
             Forces the SV to string form if it is not already.
             Will "mg_get" on "sv" if appropriate.  Always sets
             the SvUTF8 flag to avoid future validity checks even
             if the whole string is the same in UTF-8 as not.
             Returns the number of bytes in the converted string

             This is not as a general purpose byte encoding to
             Unicode interface: use the Encode extension for
             that.

                     STRLEN  sv_utf8_upgrade(SV *sv)

     sv_utf8_upgrade_flags
             Converts the PV of an SV to its UTF-8-encoded form.
             Forces the SV to string form if it is not already.
             Always sets the SvUTF8 flag to avoid future validity
             checks even if all the bytes are invariant in UTF-8.
             If "flags" has "SV_GMAGIC" bit set, will "mg_get" on
             "sv" if appropriate, else not.  Returns the number
             of bytes in the converted string "sv_utf8_upgrade"



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             and "sv_utf8_upgrade_nomg" are implemented in terms
             of this function.

             This is not as a general purpose byte encoding to
             Unicode interface: use the Encode extension for
             that.

                     STRLEN  sv_utf8_upgrade_flags(SV *const sv, const I32 flags)

     sv_utf8_upgrade_nomg
             Like sv_utf8_upgrade, but doesn't do magic on "sv"

                     STRLEN  sv_utf8_upgrade_nomg(SV *sv)

     sv_vcatpvf
             Processes its arguments like "vsprintf" and appends
             the formatted output to an SV.  Does not handle
             'set' magic.  See "sv_vcatpvf_mg".

             Usually used via its frontend "sv_catpvf".

                     void    sv_vcatpvf(SV *const sv, const char *const pat, va_list *const args)

     sv_vcatpvfn
             Processes its arguments like "vsprintf" and appends
             the formatted output to an SV.  Uses an array of SVs
             if the C style variable argument list is missing
             (NULL).  When running with taint checks enabled,
             indicates via "maybe_tainted" if results are
             untrustworthy (often due to the use of locales).

             Usually used via one of its frontends "sv_vcatpvf"
             and "sv_vcatpvf_mg".

                     void    sv_vcatpvfn(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const I32 svmax, bool *const maybe_tainted)

     sv_vcatpvf_mg
             Like "sv_vcatpvf", but also handles 'set' magic.

             Usually used via its frontend "sv_catpvf_mg".

                     void    sv_vcatpvf_mg(SV *const sv, const char *const pat, va_list *const args)

     sv_vsetpvf
             Works like "sv_vcatpvf" but copies the text into the
             SV instead of appending it.  Does not handle 'set'
             magic.  See "sv_vsetpvf_mg".

             Usually used via its frontend "sv_setpvf".

                     void    sv_vsetpvf(SV *const sv, const char *const pat, va_list *const args)




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     sv_vsetpvfn
             Works like "sv_vcatpvfn" but copies the text into
             the SV instead of appending it.

             Usually used via one of its frontends "sv_vsetpvf"
             and "sv_vsetpvf_mg".

                     void    sv_vsetpvfn(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const I32 svmax, bool *const maybe_tainted)

     sv_vsetpvf_mg
             Like "sv_vsetpvf", but also handles 'set' magic.

             Usually used via its frontend "sv_setpvf_mg".

                     void    sv_vsetpvf_mg(SV *const sv, const char *const pat, va_list *const args)

Unicode Support
     bytes_from_utf8
             Converts a string "s" of length "len" from UTF-8
             into native byte encoding.  Unlike "utf8_to_bytes"
             but like "bytes_to_utf8", returns a pointer to the
             newly-created string, and updates "len" to contain
             the new length.  Returns the original string if no
             conversion occurs, "len" is unchanged. Do nothing if
             "is_utf8" points to 0. Sets "is_utf8" to 0 if "s" is
             converted or consisted entirely of characters that
             are invariant in utf8 (i.e., US-ASCII on non-EBCDIC
             machines).

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

                     U8*     bytes_from_utf8(const U8 *s, STRLEN *len, bool *is_utf8)

     bytes_to_utf8
             Converts a string "s" of length "len" from the
             native encoding into UTF-8.  Returns a pointer to
             the newly-created string, and sets "len" to reflect
             the new length.

             A NUL character will be written after the end of the
             string.

             If you want to convert to UTF-8 from encodings other
             than the native (Latin1 or EBCDIC), see
             sv_recode_to_utf8().

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

                     U8*     bytes_to_utf8(const U8 *s, STRLEN *len)




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     ibcmp_utf8
             Return true if the strings s1 and s2 differ case-
             insensitively, false if not (if they are equal case-
             insensitively).  If u1 is true, the string s1 is
             assumed to be in UTF-8-encoded Unicode.  If u2 is
             true, the string s2 is assumed to be in
             UTF-8-encoded Unicode.  If u1 or u2 are false, the
             respective string is assumed to be in native 8-bit
             encoding.

             If the pe1 and pe2 are non-NULL, the scanning
             pointers will be copied in there (they will point at
             the beginning of the next character).  If the
             pointers behind pe1 or pe2 are non-NULL, they are
             the end pointers beyond which scanning will not
             continue under any circumstances.  If the byte
             lengths l1 and l2 are non-zero, s1+l1 and s2+l2 will
             be used as goal end pointers that will also stop the
             scan, and which qualify towards defining a
             successful match: all the scans that define an
             explicit length must reach their goal pointers for a
             match to succeed).

             For case-insensitiveness, the "casefolding" of
             Unicode is used instead of upper/lowercasing both
             the characters, see
             http://www.unicode.org/unicode/reports/tr21/ (Case
             Mappings).

                     I32     ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)

     is_ascii_string
             Returns true if first "len" bytes of the given
             string are ASCII (i.e. none of them even raise the
             question of UTF-8-ness).

             See also is_utf8_string(), is_utf8_string_loclen(),
             and is_utf8_string_loc().

                     bool    is_ascii_string(const U8 *s, STRLEN len)

     is_utf8_char
             Tests if some arbitrary number of bytes begins in a
             valid UTF-8 character.  Note that an INVARIANT (i.e.
             ASCII on non-EBCDIC machines) character is a valid
             UTF-8 character.  The actual number of bytes in the
             UTF-8 character will be returned if it is valid,
             otherwise 0.

                     STRLEN  is_utf8_char(const U8 *s)

     is_utf8_string



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             Returns true if first "len" bytes of the given
             string form a valid UTF-8 string, false otherwise.
             Note that 'a valid UTF-8 string' does not mean 'a
             string that contains code points above 0x7F encoded
             in UTF-8' because a valid ASCII string is a valid
             UTF-8 string.

             See also is_ascii_string(), is_utf8_string_loclen(),
             and is_utf8_string_loc().

                     bool    is_utf8_string(const U8 *s, STRLEN len)

     is_utf8_string_loc
             Like is_utf8_string() but stores the location of the
             failure (in the case of "utf8ness failure") or the
             location s+len (in the case of "utf8ness success")
             in the "ep".

             See also is_utf8_string_loclen() and
             is_utf8_string().

                     bool    is_utf8_string_loc(const U8 *s, STRLEN len, const U8 **p)

     is_utf8_string_loclen
             Like is_utf8_string() but stores the location of the
             failure (in the case of "utf8ness failure") or the
             location s+len (in the case of "utf8ness success")
             in the "ep", and the number of UTF-8 encoded
             characters in the "el".

             See also is_utf8_string_loc() and is_utf8_string().

                     bool    is_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)

     pv_uni_display
             Build to the scalar dsv a displayable version of the
             string spv, length len, the displayable version
             being at most pvlim bytes long (if longer, the rest
             is truncated and "..." will be appended).

             The flags argument can have UNI_DISPLAY_ISPRINT set
             to display isPRINT()able characters as themselves,
             UNI_DISPLAY_BACKSLASH to display the \\[nrfta\\] as
             the backslashed versions (like '\n')
             (UNI_DISPLAY_BACKSLASH is preferred over
             UNI_DISPLAY_ISPRINT for \\).  UNI_DISPLAY_QQ (and
             its alias UNI_DISPLAY_REGEX) have both
             UNI_DISPLAY_BACKSLASH and UNI_DISPLAY_ISPRINT turned
             on.

             The pointer to the PV of the dsv is returned.




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                     char*   pv_uni_display(SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim, UV flags)

     sv_cat_decode
             The encoding is assumed to be an Encode object, the
             PV of the ssv is assumed to be octets in that
             encoding and decoding the input starts from the
             position which (PV + *offset) pointed to.  The dsv
             will be concatenated the decoded UTF-8 string from
             ssv.  Decoding will terminate when the string tstr
             appears in decoding output or the input ends on the
             PV of the ssv. The value which the offset points
             will be modified to the last input position on the
             ssv.

             Returns TRUE if the terminator was found, else
             returns FALSE.

                     bool    sv_cat_decode(SV* dsv, SV *encoding, SV *ssv, int *offset, char* tstr, int tlen)

     sv_recode_to_utf8
             The encoding is assumed to be an Encode object, on
             entry the PV of the sv is assumed to be octets in
             that encoding, and the sv will be converted into
             Unicode (and UTF-8).

             If the sv already is UTF-8 (or if it is not POK), or
             if the encoding is not a reference, nothing is done
             to the sv.  If the encoding is not an "Encode::XS"
             Encoding object, bad things will happen.  (See
             lib/encoding.pm and Encode).

             The PV of the sv is returned.

                     char*   sv_recode_to_utf8(SV* sv, SV *encoding)

     sv_uni_display
             Build to the scalar dsv a displayable version of the
             scalar sv, the displayable version being at most
             pvlim bytes long (if longer, the rest is truncated
             and "..." will be appended).

             The flags argument is as in pv_uni_display().

             The pointer to the PV of the dsv is returned.

                     char*   sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)

     to_utf8_case
             The "p" contains the pointer to the UTF-8 string
             encoding the character that is being converted.

             The "ustrp" is a pointer to the character buffer to



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             put the conversion result to.  The "lenp" is a
             pointer to the length of the result.

             The "swashp" is a pointer to the swash to use.

             Both the special and normal mappings are stored
             lib/unicore/To/Foo.pl, and loaded by SWASHNEW, using
             lib/utf8_heavy.pl.  The special (usually, but not
             always, a multicharacter mapping), is tried first.

             The "special" is a string like "utf8::ToSpecLower",
             which means the hash %utf8::ToSpecLower.  The access
             to the hash is through Perl_to_utf8_case().

             The "normal" is a string like "ToLower" which means
             the swash %utf8::ToLower.

                     UV      to_utf8_case(const U8 *p, U8* ustrp, STRLEN *lenp, SV **swashp, const char *normal, const char *special)

     to_utf8_fold
             Convert the UTF-8 encoded character at p to its
             foldcase version and store that in UTF-8 in ustrp
             and its length in bytes in lenp.  Note that the
             ustrp needs to be at least UTF8_MAXBYTES_CASE+1
             bytes since the foldcase version may be longer than
             the original character (up to three characters).

             The first character of the foldcased version is
             returned (but note, as explained above, that there
             may be more.)

                     UV      to_utf8_fold(const U8 *p, U8* ustrp, STRLEN *lenp)

     to_utf8_lower
             Convert the UTF-8 encoded character at p to its
             lowercase version and store that in UTF-8 in ustrp
             and its length in bytes in lenp.  Note that the
             ustrp needs to be at least UTF8_MAXBYTES_CASE+1
             bytes since the lowercase version may be longer than
             the original character.

             The first character of the lowercased version is
             returned (but note, as explained above, that there
             may be more.)

                     UV      to_utf8_lower(const U8 *p, U8* ustrp, STRLEN *lenp)

     to_utf8_title
             Convert the UTF-8 encoded character at p to its
             titlecase version and store that in UTF-8 in ustrp
             and its length in bytes in lenp.  Note that the
             ustrp needs to be at least UTF8_MAXBYTES_CASE+1



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             bytes since the titlecase version may be longer than
             the original character.

             The first character of the titlecased version is
             returned (but note, as explained above, that there
             may be more.)

                     UV      to_utf8_title(const U8 *p, U8* ustrp, STRLEN *lenp)

     to_utf8_upper
             Convert the UTF-8 encoded character at p to its
             uppercase version and store that in UTF-8 in ustrp
             and its length in bytes in lenp.  Note that the
             ustrp needs to be at least UTF8_MAXBYTES_CASE+1
             bytes since the uppercase version may be longer than
             the original character.

             The first character of the uppercased version is
             returned (but note, as explained above, that there
             may be more.)

                     UV      to_utf8_upper(const U8 *p, U8* ustrp, STRLEN *lenp)

     utf8n_to_uvchr
             flags

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

             Allows length and flags to be passed to low level
             routine.

                     UV      utf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, U32 flags)

     utf8n_to_uvuni
             Bottom level UTF-8 decode routine.  Returns the
             Unicode code point value of the first character in
             the string "s" which is assumed to be in UTF-8
             encoding and no longer than "curlen"; "retlen" will
             be set to the length, in bytes, of that character.

             If "s" does not point to a well-formed UTF-8
             character, the behaviour is dependent on the value
             of "flags": if it contains UTF8_CHECK_ONLY, it is
             assumed that the caller will raise a warning, and
             this function will silently just set "retlen" to
             "-1" and return zero.  If the "flags" does not
             contain UTF8_CHECK_ONLY, warnings about
             malformations will be given, "retlen" will be set to
             the expected length of the UTF-8 character in bytes,



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             and zero will be returned.

             The "flags" can also contain various flags to allow
             deviations from the strict UTF-8 encoding (see
             utf8.h).

             Most code should use utf8_to_uvchr() rather than
             call this directly.

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

     utf8_distance
             Returns the number of UTF-8 characters between the
             UTF-8 pointers "a" and "b".

             WARNING: use only if you *know* that the pointers
             point inside the same UTF-8 buffer.

                     IV      utf8_distance(const U8 *a, const U8 *b)

     utf8_hop
             Return the UTF-8 pointer "s" displaced by "off"
             characters, either forward or backward.

             WARNING: do not use the following unless you *know*
             "off" is within the UTF-8 data pointed to by "s"
             *and* that on entry "s" is aligned on the first byte
             of character or just after the last byte of a
             character.

                     U8*     utf8_hop(const U8 *s, I32 off)

     utf8_length
             Return the length of the UTF-8 char encoded string
             "s" in characters.  Stops at "e" (inclusive).  If "e
             < s" or if the scan would end up past "e", croaks.

                     STRLEN  utf8_length(const U8* s, const U8 *e)

     utf8_to_bytes
             Converts a string "s" of length "len" from UTF-8
             into native byte encoding.  Unlike "bytes_to_utf8",
             this over-writes the original string, and updates
             len to contain the new length.  Returns zero on
             failure, setting "len" to -1.

             If you need a copy of the string, see
             "bytes_from_utf8".

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




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                     U8*     utf8_to_bytes(U8 *s, STRLEN *len)

     utf8_to_uvchr
             Returns the native character value of the first
             character in the string "s" which is assumed to be
             in UTF-8 encoding; "retlen" will be set to the
             length, in bytes, of that character.

             If "s" does not point to a well-formed UTF-8
             character, zero is returned and retlen is set, if
             possible, to -1.

                     UV      utf8_to_uvchr(const U8 *s, STRLEN *retlen)

     utf8_to_uvuni
             Returns the Unicode code point of the first
             character in the string "s" which is assumed to be
             in UTF-8 encoding; "retlen" will be set to the
             length, in bytes, of that character.

             This function should only be used when the returned
             UV is considered an index into the Unicode semantic
             tables (e.g. swashes).

             If "s" does not point to a well-formed UTF-8
             character, zero is returned and retlen is set, if
             possible, to -1.

                     UV      utf8_to_uvuni(const U8 *s, STRLEN *retlen)

     uvchr_to_utf8
             Adds the UTF-8 representation of the Native
             codepoint "uv" to the end of the string "d"; "d"
             should be have at least "UTF8_MAXBYTES+1" free bytes
             available. The return value is the pointer to the
             byte after the end of the new character. In other
             words,

                 d = uvchr_to_utf8(d, uv);

             is the recommended wide native character-aware way
             of saying

                 *(d++) = uv;

                     U8*     uvchr_to_utf8(U8 *d, UV uv)

     uvuni_to_utf8_flags
             Adds the UTF-8 representation of the Unicode
             codepoint "uv" to the end of the string "d"; "d"
             should be have at least "UTF8_MAXBYTES+1" free bytes
             available. The return value is the pointer to the



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             byte after the end of the new character. In other
             words,

                 d = uvuni_to_utf8_flags(d, uv, flags);

             or, in most cases,

                 d = uvuni_to_utf8(d, uv);

             (which is equivalent to)

                 d = uvuni_to_utf8_flags(d, uv, 0);

             is the recommended Unicode-aware way of saying

                 *(d++) = uv;

                     U8*     uvuni_to_utf8_flags(U8 *d, UV uv, UV flags)

Variables created by "xsubpp" and "xsubpp" internal functions

     ax      Variable which is setup by "xsubpp" to indicate the
             stack base offset, used by the "ST", "XSprePUSH" and
             "XSRETURN" macros.  The "dMARK" macro must be called
             prior to setup the "MARK" variable.

                     I32     ax

     CLASS   Variable which is setup by "xsubpp" to indicate the
             class name for a C++ XS constructor.  This is always
             a "char*".  See "THIS".

                     char*   CLASS

     dAX     Sets up the "ax" variable.  This is usually handled
             automatically by "xsubpp" by calling "dXSARGS".

                             dAX;

     dAXMARK Sets up the "ax" variable and stack marker variable
             "mark".  This is usually handled automatically by
             "xsubpp" by calling "dXSARGS".

                             dAXMARK;

     dITEMS  Sets up the "items" variable.  This is usually
             handled automatically by "xsubpp" by calling
             "dXSARGS".

                             dITEMS;

     dUNDERBAR



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             Sets up the "padoff_du" variable for an XSUB that
             wishes to use "UNDERBAR".

                             dUNDERBAR;

     dXSARGS Sets up stack and mark pointers for an XSUB, calling
             dSP and dMARK.  Sets up the "ax" and "items"
             variables by calling "dAX" and "dITEMS".  This is
             usually handled automatically by "xsubpp".

                             dXSARGS;

     dXSI32  Sets up the "ix" variable for an XSUB which has
             aliases.  This is usually handled automatically by
             "xsubpp".

                             dXSI32;

     items   Variable which is setup by "xsubpp" to indicate the
             number of items on the stack.  See "Variable-length
             Parameter Lists" in perlxs.

                     I32     items

     ix      Variable which is setup by "xsubpp" to indicate
             which of an XSUB's aliases was used to invoke it.
             See "The ALIAS: Keyword" in perlxs.

                     I32     ix

     newXSproto
             Used by "xsubpp" to hook up XSUBs as Perl subs.
             Adds Perl prototypes to the subs.

     RETVAL  Variable which is setup by "xsubpp" to hold the
             return value for an XSUB. This is always the proper
             type for the XSUB. See "The RETVAL Variable" in
             perlxs.

                     (whatever)      RETVAL

     ST      Used to access elements on the XSUB's stack.

                     SV*     ST(int ix)

     THIS    Variable which is setup by "xsubpp" to designate the
             object in a C++ XSUB.  This is always the proper
             type for the C++ object.  See "CLASS" and "Using XS
             With C++" in perlxs.

                     (whatever)      THIS




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     UNDERBAR
             The SV* corresponding to the $_ variable. Works even
             if there is a lexical $_ in scope.

     XS      Macro to declare an XSUB and its C parameter list.
             This is handled by "xsubpp".

     XS_VERSION
             The version identifier for an XS module.  This is
             usually handled automatically by
             "ExtUtils::MakeMaker".  See "XS_VERSION_BOOTCHECK".

     XS_VERSION_BOOTCHECK
             Macro to verify that a PM module's $VERSION variable
             matches the XS module's "XS_VERSION" variable.  This
             is usually handled automatically by "xsubpp".  See
             "The VERSIONCHECK: Keyword" in perlxs.

                             XS_VERSION_BOOTCHECK;

Warning and Dieing
     croak   This is the XSUB-writer's interface to Perl's "die"
             function.  Normally call this function the same way
             you call the C "printf" function.  Calling "croak"
             returns control directly to Perl, sidestepping the
             normal C order of execution. See "warn".

             If you want to throw an exception object, assign the
             object to $@ and then pass "NULL" to croak():

                errsv = get_sv("@", GV_ADD);
                sv_setsv(errsv, exception_object);
                croak(NULL);

                     void    croak(const char* pat, ...)

     warn    This is the XSUB-writer's interface to Perl's "warn"
             function.  Call this function the same way you call
             the C "printf" function.  See "croak".

                     void    warn(const char* pat, ...)

Undocumented functions
     These functions are currently undocumented:

     GetVars
     Gv_AMupdate
     PerlIO_clearerr
     PerlIO_close
     PerlIO_context_layers
     PerlIO_eof
     PerlIO_error



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     PerlIO_fileno
     PerlIO_fill
     PerlIO_flush
     PerlIO_get_base
     PerlIO_get_bufsiz
     PerlIO_get_cnt
     PerlIO_get_ptr
     PerlIO_read
     PerlIO_seek
     PerlIO_set_cnt
     PerlIO_set_ptrcnt
     PerlIO_setlinebuf
     PerlIO_stderr
     PerlIO_stdin
     PerlIO_stdout
     PerlIO_tell
     PerlIO_unread
     PerlIO_write
     Slab_Alloc
     Slab_Free
     amagic_call
     any_dup
     apply_attrs_string
     atfork_lock
     atfork_unlock
     av_arylen_p
     av_iter_p
     block_gimme
     call_atexit
     call_list
     calloc
     cast_i32
     cast_iv
     cast_ulong
     cast_uv
     ck_warner
     ck_warner_d
     ckwarn
     ckwarn_d
     croak_nocontext
     csighandler
     custom_op_desc
     custom_op_name
     cx_dump
     cx_dup
     cxinc
     deb
     deb_nocontext
     debop
     debprofdump
     debstack
     debstackptrs



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     delimcpy
     despatch_signals
     die
     die_nocontext
     dirp_dup
     do_aspawn
     do_binmode
     do_close
     do_gv_dump
     do_gvgv_dump
     do_hv_dump
     do_join
     do_magic_dump
     do_op_dump
     do_open
     do_open9
     do_openn
     do_pmop_dump
     do_spawn
     do_spawn_nowait
     do_sprintf
     do_sv_dump
     doing_taint
     doref
     dounwind
     dowantarray
     dump_all
     dump_eval
     dump_fds
     dump_form
     dump_indent
     dump_mstats
     dump_packsubs
     dump_sub
     dump_vindent
     fetch_cop_label
     filter_add
     filter_del
     filter_read
     find_rundefsvoffset
     form_nocontext
     fp_dup
     fprintf_nocontext
     free_global_struct
     free_tmps
     get_context
     get_mstats
     get_op_descs
     get_op_names
     get_ppaddr
     get_vtbl
     gp_dup



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     gp_free
     gp_ref
     gv_AVadd
     gv_HVadd
     gv_IOadd
     gv_SVadd
     gv_add_by_type
     gv_autoload4
     gv_check
     gv_dump
     gv_efullname
     gv_efullname3
     gv_efullname4
     gv_fetchfile
     gv_fetchfile_flags
     gv_fetchmethod_flags
     gv_fetchpv
     gv_fetchpvn_flags
     gv_fetchsv
     gv_fullname
     gv_fullname3
     gv_fullname4
     gv_handler
     gv_init
     gv_name_set
     he_dup
     hek_dup
     hv_common
     hv_common_key_len
     hv_delayfree_ent
     hv_eiter_p
     hv_eiter_set
     hv_free_ent
     hv_ksplit
     hv_name_set
     hv_placeholders_get
     hv_placeholders_p
     hv_placeholders_set
     hv_riter_p
     hv_riter_set
     hv_store_flags
     ibcmp
     ibcmp_locale
     init_global_struct
     init_i18nl10n
     init_i18nl14n
     init_stacks
     init_tm
     instr
     is_lvalue_sub
     is_uni_alnum
     is_uni_alnum_lc



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     is_uni_alpha
     is_uni_alpha_lc
     is_uni_ascii
     is_uni_ascii_lc
     is_uni_cntrl
     is_uni_cntrl_lc
     is_uni_digit
     is_uni_digit_lc
     is_uni_graph
     is_uni_graph_lc
     is_uni_idfirst
     is_uni_idfirst_lc
     is_uni_lower
     is_uni_lower_lc
     is_uni_print
     is_uni_print_lc
     is_uni_punct
     is_uni_punct_lc
     is_uni_space
     is_uni_space_lc
     is_uni_upper
     is_uni_upper_lc
     is_uni_xdigit
     is_uni_xdigit_lc
     is_utf8_alnum
     is_utf8_alpha
     is_utf8_ascii
     is_utf8_cntrl
     is_utf8_digit
     is_utf8_graph
     is_utf8_idcont
     is_utf8_idfirst
     is_utf8_lower
     is_utf8_mark
     is_utf8_perl_space
     is_utf8_perl_word
     is_utf8_posix_digit
     is_utf8_print
     is_utf8_punct
     is_utf8_space
     is_utf8_upper
     is_utf8_xdigit
     leave_scope
     load_module_nocontext
     magic_dump
     malloc
     markstack_grow
     mess
     mess_nocontext
     mfree
     mg_dup
     mg_size



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     mini_mktime
     moreswitches
     mro_get_from_name
     mro_get_private_data
     mro_register
     mro_set_mro
     mro_set_private_data
     my_atof
     my_atof2
     my_bcopy
     my_bzero
     my_chsize
     my_cxt_index
     my_cxt_init
     my_dirfd
     my_exit
     my_failure_exit
     my_fflush_all
     my_fork
     my_htonl
     my_lstat
     my_memcmp
     my_memset
     my_ntohl
     my_pclose
     my_popen
     my_popen_list
     my_setenv
     my_socketpair
     my_stat
     my_strftime
     my_strlcat
     my_strlcpy
     my_swap
     newANONATTRSUB
     newANONHASH
     newANONLIST
     newANONSUB
     newASSIGNOP
     newATTRSUB
     newAVREF
     newBINOP
     newCONDOP
     newCVREF
     newFORM
     newFOROP
     newGIVENOP
     newGVOP
     newGVREF
     newGVgen
     newHVREF
     newHVhv



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     newIO
     newLISTOP
     newLOGOP
     newLOOPEX
     newLOOPOP
     newMYSUB
     newNULLLIST
     newOP
     newPADOP
     newPMOP
     newPROG
     newPVOP
     newRANGE
     newRV
     newSLICEOP
     newSTATEOP
     newSUB
     newSVOP
     newSVREF
     newSVpvf_nocontext
     newUNOP
     newWHENOP
     newWHILEOP
     newXS_flags
     new_collate
     new_ctype
     new_numeric
     new_stackinfo
     ninstr
     op_dump
     op_free
     op_null
     op_refcnt_lock
     op_refcnt_unlock
     parser_dup
     perl_alloc_using
     perl_clone_using
     pmop_dump
     pop_scope
     pregcomp
     pregexec
     pregfree
     pregfree2
     printf_nocontext
     ptr_table_clear
     ptr_table_fetch
     ptr_table_free
     ptr_table_new
     ptr_table_split
     ptr_table_store
     push_scope
     re_compile



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     re_dup_guts
     re_intuit_start
     re_intuit_string
     realloc
     reentrant_free
     reentrant_init
     reentrant_retry
     reentrant_size
     ref
     reg_named_buff_all
     reg_named_buff_exists
     reg_named_buff_fetch
     reg_named_buff_firstkey
     reg_named_buff_nextkey
     reg_named_buff_scalar
     regclass_swash
     regdump
     regdupe_internal
     regexec_flags
     regfree_internal
     reginitcolors
     regnext
     repeatcpy
     rninstr
     rsignal
     rsignal_state
     runops_debug
     runops_standard
     rvpv_dup
     safesyscalloc
     safesysfree
     safesysmalloc
     safesysrealloc
     save_I16
     save_I32
     save_I8
     save_adelete
     save_aelem
     save_aelem_flags
     save_alloc
     save_aptr
     save_ary
     save_bool
     save_clearsv
     save_delete
     save_destructor
     save_destructor_x
     save_freepv
     save_freesv
     save_generic_pvref
     save_generic_svref
     save_gp



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     save_hash
     save_hdelete
     save_helem
     save_helem_flags
     save_hptr
     save_int
     save_item
     save_iv
     save_list
     save_long
     save_mortalizesv
     save_nogv
     save_padsv_and_mortalize
     save_pptr
     save_pushptr
     save_re_context
     save_scalar
     save_set_svflags
     save_shared_pvref
     save_sptr
     save_svref
     save_vptr
     savestack_grow
     savestack_grow_cnt
     scan_num
     scan_vstring
     screaminstr
     seed
     set_context
     set_numeric_local
     set_numeric_radix
     set_numeric_standard
     share_hek
     si_dup
     ss_dup
     stack_grow
     start_subparse
     stashpv_hvname_match
     str_to_version
     sv_2iv
     sv_2pv
     sv_2uv
     sv_catpvf_mg_nocontext
     sv_catpvf_nocontext
     sv_compile_2op
     sv_dump
     sv_dup
     sv_peek
     sv_pvn_nomg
     sv_setpvf_mg_nocontext
     sv_setpvf_nocontext
     sv_utf8_upgrade_flags_grow



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     swash_fetch
     swash_init
     sys_init
     sys_init3
     sys_intern_clear
     sys_intern_dup
     sys_intern_init
     sys_term
     taint_env
     taint_proper
     tmps_grow
     to_uni_fold
     to_uni_lower
     to_uni_lower_lc
     to_uni_title
     to_uni_title_lc
     to_uni_upper
     to_uni_upper_lc
     unlnk
     unsharepvn
     utf16_to_utf8
     utf16_to_utf8_reversed
     uvchr_to_utf8_flags
     uvuni_to_utf8
     vcroak
     vdeb
     vform
     vload_module
     vmess
     vnewSVpvf
     vwarn
     vwarner
     warn_nocontext
     warner
     warner_nocontext
     whichsig

AUTHORS
     Until May 1997, this document was maintained by Jeff Okamoto
     <okamoto@corp.hp.com>.  It is now maintained as part of Perl
     itself.

     With lots of help and suggestions from Dean Roehrich,
     Malcolm Beattie, Andreas Koenig, Paul Hudson, Ilya
     Zakharevich, Paul Marquess, Neil Bowers, Matthew Green, Tim
     Bunce, Spider Boardman, Ulrich Pfeifer, Stephen McCamant,
     and Gurusamy Sarathy.

     API Listing originally by Dean Roehrich <roehrich@cray.com>.

     Updated to be autogenerated from comments in the source by
     Benjamin Stuhl.



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ATTRIBUTES
     See attributes(5) for descriptions of the following
     attributes:

     +---------------+------------------+
     |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
     +---------------+------------------+
     |Availability   | runtime/perl-512 |
     +---------------+------------------+
     |Stability      | Uncommitted      |
     +---------------+------------------+
SEE ALSO
     perlguts, perlxs, perlxstut, perlintern



NOTES
     This software was built from source available at
     https://java.net/projects/solaris-userland.  The original
     community source was downloaded from
     http://www.cpan.org/src/5.0/perl-5.12.5.tar.bz2

     Further information about this software can be found on the
     open source community website at http://www.perl.org/.































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