PERLAPI(1) 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.
The listing 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
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* ar)
av_delete
Deletes the element indexed by "key" from the array. Returns the deleted element. "flags" is currently ignored.
SV* av_delete(AV* ar, 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* ar, I32 key)
av_extend
Pre-extend an array. The "key" is the index to which the array should be extended.
void av_extend(AV* ar, 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* ar, I32 key, I32 lval)
av_fill Ensure than an array has a given number of elements, equivalent to Perl's "$#array = $fill;".
void av_fill(AV* ar, I32 fill)
av_len Returns the highest index in the array. Returns -1 if the array is empty.
I32 av_len(AV* ar)
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** svp)
av_pop Pops an SV off the end of the array. Returns &PL_sv_undef if the array is empty.
SV* av_pop(AV* ar)
av_push Pushes an SV onto the end of the array. The array will grow automatically to accommodate the addition.
void av_push(AV* ar, SV* val)
av_shift
Shifts an SV off the beginning of the array.
SV* av_shift(AV* ar)
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* ar, I32 key, SV* val)
av_undef
Undefines the array. Frees the memory used by the array itself.
void av_undef(AV* ar)
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* ar, I32 num)
get_av Returns the AV of the specified Perl array. If "create" is set and the Perl variable does not exist then it will be created. If
"create" is not set 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 create)
newAV Creates a new AV. The reference count is set to 1.
AV* newAV()
Nullav Null AV pointer.
sortsv Sort an array. Here is an example:
sortsv(AvARRAY(av), av_len(av)+1, Perl_sv_cmp_locale);
See lib/sort.pm for details about controlling the sorting algorithm.
void sortsv(SV ** array, size_t num_elts, SVCOMPARE_t cmp)
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)
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, I32 flags)
ENTER Opening bracket on a callback. See "LEAVE" and perlcall.
ENTER;
eval_pv Tells Perl to "eval" the given string and return an SV* result.
NOTE: the perl_ form of this function is deprecated.
SV* eval_pv(const char* p, I32 croak_on_error)
eval_sv Tells Perl to "eval" the string in the SV.
NOTE: the perl_ form of this function is deprecated.
I32 eval_sv(SV* sv, I32 flags)
FREETMPS
Closing bracket for temporaries on a callback. See "SAVETMPS" and perlcall.
FREETMPS;
LEAVE Closing bracket on a callback. See "ENTER" and perlcall.
LEAVE;
SAVETMPS
Opening bracket for temporaries on a callback. See "FREETMPS" and perlcall.
SAVETMPS;
Character classes
isALNUM Returns a boolean indicating whether the C "char" is an ASCII alphanumeric character (including underscore) or digit.
bool isALNUM(char ch)
isALPHA Returns a boolean indicating whether the C "char" is an ASCII alphabetic character.
bool isALPHA(char ch)
isDIGIT Returns a boolean indicating whether the C "char" is an ASCII digit.
bool isDIGIT(char ch)
isLOWER Returns a boolean indicating whether the C "char" is a lowercase character.
bool isLOWER(char ch)
isSPACE Returns a boolean indicating whether the C "char" is whitespace.
bool isSPACE(char ch)
isUPPER Returns a boolean indicating whether the C "char" is an uppercase character.
bool isUPPER(char ch)
toLOWER Converts the specified character to lowercase.
char toLOWER(char ch)
toUPPER Converts the specified character to uppercase.
char toUPPER(char ch)
Cloning an interpreter
perl_clone
Create and return a new interpreter by cloning the current one.
perl_clone takes these flags as paramters:
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->new 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 ref-
count. 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 inter-
preter and then throw it away and return to the original one, you don't need to do anything.
PerlInterpreter* perl_clone(PerlInterpreter* interp, UV flags)
CV Manipulation Functions
CvSTASH Returns the stash of the CV.
HV* CvSTASH(CV* cv)
get_cv Returns the CV of the specified Perl subroutine. If "create" is set and the Perl subroutine does not exist then it will be
declared (which has the same effect as saying "sub name;"). If "create" is not set and the subroutine does not exist then NULL is
returned.
NOTE: the perl_ form of this function is deprecated.
CV* get_cv(const char* name, I32 create)
Nullcv Null CV pointer.
Embedding Functions
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_LOAD-
MOD_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".
void load_module(U32 flags, SV* name, SV* ver, ...)
nothreadhook
Stub that provides thread hook for perl_destruct when there are no threads.
int nothreadhook()
perl_alloc
Allocates a new Perl interpreter. See perlembed.
PerlInterpreter* perl_alloc()
perl_construct
Initializes a new Perl interpreter. See perlembed.
void perl_construct(PerlInterpreter* interp)
perl_destruct
Shuts down a Perl interpreter. See perlembed.
int perl_destruct(PerlInterpreter* interp)
perl_free
Releases a Perl interpreter. See perlembed.
void perl_free(PerlInterpreter* interp)
perl_parse
Tells a Perl interpreter to parse a Perl script. See perlembed.
int perl_parse(PerlInterpreter* interp, XSINIT_t xsinit, int argc, char** argv, char** env)
perl_run
Tells a Perl interpreter to run. See perlembed.
int perl_run(PerlInterpreter* interp)
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 Perl_load_module instead.
NOTE: the perl_ form of this function is deprecated.
void require_pv(const char* pv)
Functions in file pp_pack.c
pack_cat
The engine implementing pack() Perl function.
void pack_cat(SV *cat, char *pat, char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags)
unpack_str
The engine implementing unpack() Perl function.
I32 unpack_str(char *pat, char *patend, char *s, char *strbeg, char *strend, char **new_s, I32 ocnt, U32 flags)
Global 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_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
GV Functions
GvSV Return the SV from the GV.
SV* GvSV(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. Similarly for
all the searched stashes.
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
See gv_fetchmethod_autoload.
GV* gv_fetchmethod(HV* stash, const char* name)
gv_fetchmethod_autoload
Returns the glob which contains the subroutine to call to invoke the method on the "stash". In fact in the presence of autoloading
this may be the glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD is already setup.
The third parameter of "gv_fetchmethod_autoload" determines whether AUTOLOAD lookup is performed if the given method is not
present: non-zero means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD. Calling "gv_fetchmethod" is equivalent to
calling "gv_fetchmethod_autoload" with a non-zero "autoload" parameter.
These functions grant "SUPER" token as a prefix of the method name. Note that if you want to keep the returned glob for a long
time, you need to check for it being "AUTOLOAD", since at the later time the call may load a different subroutine due to $AUTOLOAD
changing its value. Use the glob created via a side effect to do this.
These functions have the same side-effects and as "gv_fetchmeth" with "level==0". "name" should be writable if contains ':' or "'
''". The warning against passing the GV returned by "gv_fetchmeth" to "call_sv" apply equally to these functions.
GV* gv_fetchmethod_autoload(HV* stash, const char* name, I32 autoload)
gv_fetchmeth_autoload
Same as gv_fetchmeth(), but looks for autoloaded subroutines too. Returns a glob for the subroutine.
For an autoloaded subroutine without a GV, will create a GV even if "level < 0". For an autoloaded subroutine without a stub,
GvCV() of the result may be zero.
GV* gv_fetchmeth_autoload(HV* stash, const char* name, STRLEN len, I32 level)
gv_stashpv
Returns a pointer to the stash for a specified package. "name" should be a valid UTF-8 string. If "create" is set then the pack-
age will be created if it does not already exist. If "create" is not set and the package does not exist then NULL is returned.
HV* gv_stashpv(const char* name, I32 create)
gv_stashsv
Returns a pointer to the stash for a specified package, which must be a valid UTF-8 string. See "gv_stashpv".
HV* gv_stashsv(SV* sv, I32 create)
Handy Values
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).
Nullch Null character pointer. =for hackers Found in file handy.h
Nullsv Null SV pointer.
Hash Manipulation Functions
get_hv Returns the HV of the specified Perl hash. If "create" is set and the Perl variable does not exist then it will be created. If
"create" is not set 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 create)
HeHASH Returns the computed hash stored in the hash entry.
U32 HeHASH(HE* he)
HeKEY Returns the actual pointer stored in the key slot of the hash entry. The pointer may be either "char*" or "SV*", depending on the
value of "HeKLEN()". Can be assigned to. The "HePV()" or "HeSVKEY()" macros are usually preferable for finding the value of a
key.
void* HeKEY(HE* he)
HeKLEN If this is negative, and amounts to "HEf_SVKEY", it indicates the entry holds an "SV*" key. Otherwise, holds the actual length of
the key. Can be assigned to. The "HePV()" macro is usually preferable for finding key lengths.
STRLEN HeKLEN(HE* he)
HePV Returns the key slot of the hash entry as a "char*" value, doing any necessary dereferencing of possibly "SV*" keys. The length of
the string is placed in "len" (this is a macro, so do not use &len). If you do not care about what the length of the key is, you
may use the global variable "PL_na", though this is rather less efficient than using a local variable. Remember though, that hash
keys in perl are free to contain embedded nulls, so using "strlen()" or similar is not a good way to find the length of hash keys.
This is very similar to the "SvPV()" macro described elsewhere in this document.
char* HePV(HE* he, STRLEN len)
HeSVKEY Returns the key as an "SV*", or "Nullsv" 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)
HeVAL Returns the value slot (type "SV*") stored in the hash entry.
SV* HeVAL(HE* he)
HvNAME Returns the package name of a stash. See "SvSTASH", "CvSTASH".
char* HvNAME(HV* stash)
hv_clear
Clears a hash, making it empty.
void hv_clear(HV* tb)
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* tb, const char* key, I32 klen, I32 flags)
hv_delete_ent
Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. The "flags" value will
normally be zero; if set to G_DISCARD then NULL will be returned. "hash" can be a valid precomputed hash value, or 0 to ask for it
to be computed.
SV* hv_delete_ent(HV* tb, SV* key, 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* tb, 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* tb, SV* key, 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* tb, const char* key, I32 klen, 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* tb, SV* key, I32 lval, U32 hash)
hv_iterinit
Prepares a starting point to traverse a hash table. Returns the number of keys in the hash (i.e. the same as "HvKEYS(tb)"). The
return value is currently only meaningful for hashes without tie magic.
NOTE: Before version 5.004_65, "hv_iterinit" used to return the number of hash buckets that happen to be in use. If you still need
that esoteric value, you can get it through the macro "HvFILL(tb)".
I32 hv_iterinit(HV* tb)
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 itera-
tor immediately else the entry will leak - call "hv_iternext" to trigger the resource deallocation.
HE* hv_iternext(HV* tb)
hv_iternextsv
Performs an "hv_iternext", "hv_iterkey", and "hv_iterval" in one operation.
SV* hv_iternextsv(HV* hv, char** key, I32* retlen)
hv_iternext_flags
Returns entries from a hash iterator. See "hv_iterinit" and "hv_iternext". The "flags" value will normally be zero; if
HV_ITERNEXT_WANTPLACEHOLDERS is set the placeholders keys (for restricted hashes) will be returned in addition to normal keys. By
default placeholders are automatically skipped over. Currently a placeholder is implemented with a value that is literally
<&Perl_sv_undef> (a regular "undef" value is a normal read-write SV for which "!SvOK" is false). 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* tb, I32 flags)
hv_iterval
Returns the value from the current position of the hash iterator. See "hv_iterkey".
SV* hv_iterval(HV* tb, HE* entry)
hv_magic
Adds magic to a hash. See "sv_magic".
void hv_magic(HV* hv, GV* gv, int how)
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 pre-
computed 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.
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* tb, const char* key, I32 klen, SV* val, U32 hash)
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.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied
hashes.
HE* hv_store_ent(HV* tb, SV* key, SV* val, U32 hash)
hv_undef
Undefines the hash.
void hv_undef(HV* tb)
newHV Creates a new HV. The reference count is set to 1.
HV* newHV()
Nullhv Null HV pointer.
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 "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(SV* sv, int type)
mg_free Free any magic storage used by the SV. See "sv_magic".
int mg_free(SV* sv)
mg_get Do magic after a value is retrieved from the SV. See "sv_magic".
int mg_get(SV* sv)
mg_length
Report on the SV's length. See "sv_magic".
U32 mg_length(SV* sv)
mg_magical
Turns on the magical status of an SV. See "sv_magic".
void mg_magical(SV* sv)
mg_set Do magic after a value is assigned to the SV. See "sv_magic".
int mg_set(SV* sv)
SvGETMAGIC
Invokes "mg_get" on an SV if it has 'get' magic. This macro evaluates its argument more than once.
void SvGETMAGIC(SV* sv)
SvLOCK Arranges for a mutual exclusion lock to be obtained on sv if a suitable module has been loaded.
void SvLOCK(SV* sv)
SvSETMAGIC
Invokes "mg_set" on an SV if it has 'set' magic. This macro evaluates its argument more than once.
void SvSETMAGIC(SV* sv)
SvSetMagicSV
Like "SvSetSV", but does any set magic required afterwards.
void SvSetMagicSV(SV* dsb, SV* ssv)
SvSetMagicSV_nosteal
Like "SvSetMagicSV", 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)
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)
Move The XSUB-writer's interface to the C "memmove" function. The "src" is the source, "dest" is the destination, "nitems" is the num-
ber of items, and "type" is the type. Can do overlapping moves. See also "Copy".
void Move(void* src, void* dest, int nitems, type)
New The XSUB-writer's interface to the C "malloc" function.
void New(int id, void* ptr, int nitems, type)
Newc The XSUB-writer's interface to the C "malloc" function, with cast.
void Newc(int id, void* ptr, int nitems, type, cast)
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 tailing 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. "id" is an integer id between 0 and 1299 (used to identify leaks).
SV* NEWSV(int id, STRLEN len)
Newz The XSUB-writer's interface to the C "malloc" function. The allocated memory is zeroed with "memzero".
void Newz(int id, void* ptr, int nitems, type)
Poison Fill up memory with a pattern (byte 0xAB over and over again) that hopefully catches attempts to access uninitialized memory.
void Poison(void* dest, int nitems, type)
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". The memory allocated for the new string can be freed with the "Safefree()" function.
char* savepvn(const char* pv, I32 len)
savesharedpv
A version of "savepv()" which allocates the duplicate string in memory which is shared between threads.
char* savesharedpv(const char* pv)
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)
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 "Nullch" 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* littlesv, U32 flags)
form Takes a sprintf-style format pattern and conventional (non-SV) arguments and returns the formatted string.
(char *) Perl_form(pTHX_ const char* pat, ...)
can be used any place a string (char *) is required:
char * s = Perl_form("%d.%d",major,minor);
Uses a single private buffer so if you want to format several strings you must explicitly copy the earlier strings away (and free
the copies when you are done).
char* form(const char* pat, ...)
getcwd_sv
Fill the sv with current working directory
int getcwd_sv(SV* sv)
strEQ Test two strings to see if they are equal. Returns true or false.
bool strEQ(char* s1, char* s2)
strGE Test two strings to see if the first, "s1", is greater than or equal to the second, "s2". Returns true or false.
bool strGE(char* s1, char* s2)
strGT Test two strings to see if the first, "s1", is greater than the second, "s2". Returns true or false.
bool strGT(char* s1, char* s2)
strLE Test two strings to see if the first, "s1", is less than or equal to the second, "s2". Returns true or false.
bool strLE(char* s1, char* s2)
strLT Test two strings to see if the first, "s1", is less than the second, "s2". Returns true or false.
bool strLT(char* s1, char* s2)
strNE Test two strings to see if they are different. Returns true or false.
bool strNE(char* s1, char* s2)
strnEQ Test two strings to see if they are equal. The "len" parameter indicates the number of bytes to compare. Returns true or false.
(A wrapper for "strncmp").
bool strnEQ(char* s1, char* s2, STRLEN len)
strnNE Test two strings to see if they are different. The "len" parameter indicates the number of bytes to compare. Returns true or
false. (A wrapper for "strncmp").
bool strnNE(char* s1, char* s2, STRLEN len)
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. On return *len is set to the length 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 hex 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(char* start, STRLEN* len, 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 non-hex-digit character. On return *len is set to the length 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(char* start, STRLEN* len, 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 trun-
cated to an integer), and IS_NUMBER_NEG if the number is negative (in which case *valuep holds the absolute value). IS_NUM-
BER_IN_UV is not set if e notation was used or the number is larger than a UV.
int grok_number(const char *pv, STRLEN len, UV *valuep)
grok_numeric_radix
Scan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp, const char *send)
grok_oct
UV grok_oct(char* start, STRLEN* len, I32* flags, NV *result)
scan_bin
For backwards compatibility. Use "grok_bin" instead.
NV scan_bin(char* start, STRLEN len, STRLEN* retlen)
scan_hex
For backwards compatibility. Use "grok_hex" instead.
NV scan_hex(char* start, STRLEN len, STRLEN* retlen)
scan_oct
For backwards compatibility. Use "grok_oct" instead.
NV scan_oct(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(CV* cv)
newCONSTSUB
Creates a constant sub equivalent to Perl "sub FOO () { 123 }" which is eligible for inlining at compile-time.
CV* newCONSTSUB(HV* stash, char* name, SV* sv)
newXS Used by "xsubpp" to hook up XSUBs as Perl subs.
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".
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 provide a STRLEN n_a and use POPpx.
char* POPp
POPpbytex
Pops a string off the stack which must consist of bytes i.e. characters < 256. Requires a variable STRLEN n_a in scope.
char* POPpbytex
POPpx Pops a string off the stack. Requires a variable STRLEN n_a in scope.
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. See "XPUSHi".
void PUSHi(IV iv)
PUSHMARK
Opening bracket for arguments on a callback. See "PUTBACK" and perlcall.
PUSHMARK;
PUSHn Push a double onto the stack. The stack must have room for this element. Handles 'set' magic. See "XPUSHn".
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. See "XPUSHp".
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. See "XPUSHs".
void PUSHs(SV* sv)
PUSHu Push an unsigned integer onto the stack. The stack must have room for this element. See "XPUSHu".
void PUSHu(UV uv)
PUTBACK Closing bracket for XSUB arguments. This is usually handled by "xsubpp". See "PUSHMARK" and perlcall for other uses.
PUTBACK;
SP Stack pointer. This is usually handled by "xsubpp". See "dSP" and "SPAGAIN".
SPAGAIN Refetch the stack pointer. Used after a callback. See perlcall.
SPAGAIN;
XPUSHi Push an integer onto the stack, extending the stack if necessary. Handles 'set' magic. See "PUSHi".
void XPUSHi(IV iv)
XPUSHn Push a double onto the stack, extending the stack if necessary. Handles 'set' magic. See "PUSHn".
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. See "PUSHp".
void XPUSHp(char* str, STRLEN len)
XPUSHs Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. See "PUSHs".
void XPUSHs(SV* sv)
XPUSHu Push an unsigned integer onto the stack, extending the stack if necessary. See "PUSHu".
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_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_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".
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
get_sv Returns the SV of the specified Perl scalar. If "create" is set and the Perl variable does not exist then it will be created. If
"create" is not set 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 create)
looks_like_number
Test if the content of an SV looks like a number (or is a number). "Inf" and "Infinity" are treated as numbers (so will not issue
a non-numeric warning), even if your atof() doesn't grok them.
I32 looks_like_number(SV* sv)
newRV_inc
Creates an RV wrapper for an SV. The reference count for the original SV is incremented.
SV* newRV_inc(SV* sv)
newRV_noinc
Creates an RV wrapper for an SV. The reference count for the original SV is not incremented.
SV* newRV_noinc(SV *sv)
newSV Create a new null SV, or if len > 0, create a new empty SVt_PV type SV with an initial PV allocation of len+1. Normally accessed
via the "NEWSV" macro.
SV* newSV(STRLEN len)
newSViv Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV* newSViv(IV i)
newSVnv Creates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.
SV* newSVnv(NV n)
newSVpv Creates a new SV and copies a string into it. The reference count for the SV is set to 1. If "len" is zero, Perl will compute the
length using strlen(). For efficiency, consider using "newSVpvn" instead.
SV* newSVpv(const char* s, STRLEN len)
newSVpvf
Creates a new SV and initializes it with the string formatted like "sprintf".
SV* newSVpvf(const char* pat, ...)
newSVpvn
Creates a new SV and copies a string into it. The reference count for the SV is set to 1. Note that if "len" is zero, Perl will
create a zero length string. You are responsible for ensuring that the source string is at least "len" bytes long.
SV* newSVpvn(const char* s, STRLEN len)
newSVpvn_share
Creates a new SV with its SvPVX 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. The string's hash is stored in the UV slot of the SV; if the "hash" parameter is
non-zero, that value is used; otherwise the hash is computed. The idea here is that as the string table is used for shared hash
keys these strings will have SvPVX == HeKEY and hash lookup will avoid string compare.
SV* newSVpvn_share(const char* s, I32 len, U32 hash)
newSVrv Creates a new SV for the RV, "rv", to point to. If "rv" is not an RV then it will be upgraded to one. If "classname" is non-null
then the new SV will be blessed in the specified package. The new SV is returned and its reference count is 1.
SV* newSVrv(SV* rv, const char* classname)
newSVsv Creates a new SV which is an exact duplicate of the original SV. (Uses "sv_setsv").
SV* newSVsv(SV* old)
newSVuv Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.
SV* newSVuv(UV u)
new_vstring
Returns a pointer to the next character after the parsed vstring, as well as updating the passed in sv.
Function must be called like
sv = NEWSV(92,5);
s = new_vstring(s,sv);
The sv must already be large enough to store the vstring passed in.
char* new_vstring(char *vstr, SV *sv)
SvCUR Returns the length of the string which is in the SV. See "SvLEN".
STRLEN SvCUR(SV* sv)
SvCUR_set
Set the length of the string which is in the SV. See "SvCUR".
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)
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 boolean indicating whether the SV contains an integer.
bool SvIOK(SV* sv)
SvIOKp Returns a boolean indicating whether the SV contains an integer. Checks the private setting. Use "SvIOK".
bool SvIOKp(SV* sv)
SvIOK_notUV
Returns a boolean indicating whether the SV contains a signed integer.
void SvIOK_notUV(SV* sv)
SvIOK_off
Unsets the IV status of an SV.
void SvIOK_off(SV* sv)
SvIOK_on
Tells an SV that it is an integer.
void SvIOK_on(SV* sv)
SvIOK_only
Tells an SV that it is an integer and disables all other OK bits.
void SvIOK_only(SV* sv)
SvIOK_only_UV
Tells and SV that it is an unsigned integer and disables all other OK bits.
void SvIOK_only_UV(SV* sv)
SvIOK_UV
Returns a boolean indicating whether the SV contains an unsigned integer.
void SvIOK_UV(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 Coerces the given SV to an integer and returns it. Guarantees to evaluate sv only once. Use the more efficient "SvIV" otherwise.
IV SvIVx(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)
SvLEN Returns the size of the string buffer in the SV, not including any part attributable to "SvOOK". See "SvCUR".
STRLEN SvLEN(SV* sv)
SvNIOK Returns a boolean indicating whether the SV contains a number, integer or double.
bool SvNIOK(SV* sv)
SvNIOKp Returns a boolean indicating whether the SV contains a number, integer or double. Checks the private setting. Use "SvNIOK".
bool SvNIOKp(SV* sv)
SvNIOK_off
Unsets the NV/IV status of an SV.
void SvNIOK_off(SV* sv)
SvNOK Returns a boolean indicating whether the SV contains a double.
bool SvNOK(SV* sv)
SvNOKp Returns a boolean indicating whether the SV contains a double. Checks the private setting. Use "SvNOK".
bool 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. Use the more efficient "SvNV" otherwise.
NV SvNVx(SV* sv)
SvOK Returns a boolean indicating whether the value is an SV.
bool SvOK(SV* sv)
SvOOK Returns a boolean indicating whether the SvIVX is a valid offset value for the SvPVX. This hack is used internally to speed up
removal of characters from the beginning of a SvPV. When SvOOK is true, then the start of the allocated string buffer is really
(SvPVX - SvIVX).
bool SvOOK(SV* sv)
SvPOK Returns a boolean indicating whether the SV contains a character string.
bool SvPOK(SV* sv)
SvPOKp Returns a boolean indicating whether the SV contains a character string. Checks the private setting. Use "SvPOK".
bool SvPOKp(SV* sv)
SvPOK_off
Unsets the PV status of an SV.
void SvPOK_off(SV* sv)
SvPOK_on
Tells an SV that it is a string.
void SvPOK_on(SV* sv)
SvPOK_only
Tells an SV that it is a string and disables all other OK bits. Will also turn off the UTF8 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 UTF8 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 effi-
cient "SvPVbyte" otherwise.
char* SvPVbytex(SV* sv, STRLEN len)
SvPVbytex_force
Like "SvPV_force", but converts sv to byte representation first if necessary. Guarantees to evaluate sv only once; use the more
efficient "SvPVbyte_force" otherwise.
char* SvPVbytex_force(SV* sv, STRLEN len)
SvPVbyte_force
Like "SvPV_force", but converts sv to byte representation first if necessary.
char* SvPVbyte_force(SV* sv, STRLEN len)
SvPVbyte_nolen
Like "SvPV_nolen", but converts sv to byte representation first if necessary.
char* SvPVbyte_nolen(SV* sv)
SvPVutf8
Like "SvPV", but converts sv to utf8 first if necessary.
char* SvPVutf8(SV* sv, STRLEN len)
SvPVutf8x
Like "SvPV", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficient "SvPVutf8"
otherwise.
char* SvPVutf8x(SV* sv, STRLEN len)
SvPVutf8x_force
Like "SvPV_force", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once; use the more efficient
"SvPVutf8_force" otherwise.
char* SvPVutf8x_force(SV* sv, STRLEN len)
SvPVutf8_force
Like "SvPV_force", but converts sv to utf8 first if necessary.
char* SvPVutf8_force(SV* sv, STRLEN len)
SvPVutf8_nolen
Like "SvPV_nolen", but converts sv to utf8 first if necessary.
char* SvPVutf8_nolen(SV* sv)
SvPVx A version of "SvPV" which guarantees to evaluate sv only once.
char* SvPVx(SV* sv, STRLEN len)
SvPVX Returns a pointer to the physical string in the SV. The SV must contain a string.
char* SvPVX(SV* sv)
SvPV_force
Like "SvPV" but will force the SV into containing just a string ("SvPOK_only"). You want force if you are going to update the
"SvPVX" directly.
char* SvPV_force(SV* sv, STRLEN len)
SvPV_force_nomg
Like "SvPV" but will force the SV into containing just a string ("SvPOK_only"). You want force if you are going to update the
"SvPVX" directly. Doesn't process magic.
char* SvPV_force_nomg(SV* sv, STRLEN len)
SvPV_nolen
Returns a pointer to the string in the SV, or a stringified form of the SV if the SV does not contain a string. The SV may cache
the stringified form becoming "SvPOK". Handles 'get' magic.
char* SvPV_nolen(SV* sv)
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.
SV* SvREFCNT_inc(SV* sv)
SvROK Tests if the SV is an RV.
bool SvROK(SV* sv)
SvROK_off
Unsets the RV status of an SV.
void SvROK_off(SV* sv)
SvROK_on
Tells an SV that it is an RV.
void SvROK_on(SV* sv)
SvRV Dereferences an RV to return the SV.
SV* SvRV(SV* sv)
SvSTASH Returns the stash of the SV.
HV* SvSTASH(SV* sv)
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.
void SvTAINTED_on(SV* sv)
SvTRUE Returns a boolean indicating whether Perl would evaluate the SV as true or false, defined or undefined. Does not handle 'get'
magic.
bool SvTRUE(SV* sv)
SvTYPE Returns the type of the SV. See "svtype".
svtype SvTYPE(SV* sv)
SvUNLOCK
Releases a mutual exclusion lock on sv if a suitable module has been loaded.
void SvUNLOCK(SV* sv)
SvUOK Returns a boolean indicating whether the SV contains an unsigned integer.
void 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 boolean indicating whether the SV contains UTF-8 encoded data.
void SvUTF8(SV* sv)
SvUTF8_off
Unsets the UTF8 status of an SV.
void SvUTF8_off(SV *sv)
SvUTF8_on
Turn on the UTF8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_on(SV *sv)
SvUV Coerces the given SV to an unsigned integer and returns it. See "SvUVx" for a version which guarantees to evaluate sv only once.
UV SvUV(SV* sv)
SvUVX Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sure SvIOK is true. See also
"SvUV()".
UV SvUVX(SV* sv)
SvUVx Coerces the given SV to an unsigned integer and returns it. Guarantees to evaluate sv only once. Use the more efficient "SvUV" oth-
erwise.
UV SvUVx(SV* sv)
sv_2bool
This function is only called on magical items, and is only used by sv_true() or its macro equivalent.
bool sv_2bool(SV* sv)
sv_2cv Using various gambits, try to get a CV from an SV; in addition, try if possible to set *st and *gvp to the stash and GV associated
with it.
CV* sv_2cv(SV* sv, HV** st, GV** gvp, I32 lref)
sv_2io Using various gambits, try to get an IO from an SV: the IO slot if its a GV; or the recursive result if we're an RV; or the IO slot
of the symbol named after the PV if we're a string.
IO* sv_2io(SV* sv)
sv_2iv Return the integer value of an SV, doing any necessary string conversion, magic etc. Normally used via the "SvIV(sv)" and
"SvIVx(sv)" macros.
IV sv_2iv(SV* sv)
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. See also "sv_newmortal" and "sv_mortalcopy".
SV* sv_2mortal(SV* sv)
sv_2nv Return the num value of an SV, doing any necessary string or integer conversion, magic etc. Normally used via the "SvNV(sv)" and
"SvNVx(sv)" macros.
NV sv_2nv(SV* sv)
sv_2pvbyte
Return a pointer to the byte-encoded representation of the SV, and set *lp to its length. May cause the SV to be downgraded from
UTF8 as a side-effect.
Usually accessed via the "SvPVbyte" macro.
char* sv_2pvbyte(SV* sv, STRLEN* lp)
sv_2pvbyte_nolen
Return a pointer to the byte-encoded representation of the SV. May cause the SV to be downgraded from UTF8 as a side-effect.
Usually accessed via the "SvPVbyte_nolen" macro.
char* sv_2pvbyte_nolen(SV* sv)
sv_2pvutf8
Return a pointer to the UTF8-encoded representation of the SV, and set *lp to its length. May cause the SV to be upgraded to UTF8
as a side-effect.
Usually accessed via the "SvPVutf8" macro.
char* sv_2pvutf8(SV* sv, STRLEN* lp)
sv_2pvutf8_nolen
Return a pointer to the UTF8-encoded representation of the SV. May cause the SV to be upgraded to UTF8 as a side-effect.
Usually accessed via the "SvPVutf8_nolen" macro.
char* sv_2pvutf8_nolen(SV* sv)
sv_2pv_flags
Returns a pointer to the string value of an SV, and sets *lp to its length. If flags includes SV_GMAGIC, does an mg_get() first.
Coerces sv to a string if necessary. Normally invoked via the "SvPV_flags" macro. "sv_2pv()" and "sv_2pv_nomg" usually end up here
too.
char* sv_2pv_flags(SV* sv, STRLEN* lp, I32 flags)
sv_2pv_nolen
Like "sv_2pv()", but doesn't return the length too. You should usually use the macro wrapper "SvPV_nolen(sv)" instead.
char* sv_2pv_nolen(SV* sv)
sv_2uv Return the unsigned integer value of an SV, doing any necessary string conversion, magic etc. Normally used via the "SvUV(sv)" and
"SvUVx(sv)" macros.
UV sv_2uv(SV* sv)
sv_backoff
Remove any string offset. You should normally use the "SvOOK_off" macro wrapper instead.
int sv_backoff(SV* sv)
sv_bless
Blesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (see "gv_stashpv()").
The reference count of the SV is unaffected.
SV* sv_bless(SV* sv, HV* stash)
sv_catpv
Concatenates the string onto the end of the string which is in the SV. If the SV has the UTF8 status set, then the bytes appended
should be valid UTF8. Handles 'get' magic, but not 'set' magic. See "sv_catpv_mg".
void sv_catpv(SV* sv, const char* ptr)
sv_catpvf
Processes its arguments like "sprintf" and appends the formatted output to an SV. If the appended data contains "wide" characters
(including, but not limited to, SVs with a UTF-8 PV formatted with %s, and characters >255 formatted with %c), the original SV
might get upgraded to UTF-8. Handles 'get' magic, but not 'set' magic. "SvSETMAGIC()" must typically be called after calling this
function to handle 'set' magic.
void sv_catpvf(SV* sv, const char* pat, ...)
sv_catpvf_mg
Like "sv_catpvf", but also handles 'set' magic.
void sv_catpvf_mg(SV *sv, const char* pat, ...)
sv_catpvn
Concatenates the string onto the end of the string which is in the SV. The "len" indicates number of bytes to copy. If the SV has
the UTF8 status set, then the bytes appended should be valid UTF8. Handles 'get' magic, but not 'set' magic. See "sv_catpvn_mg".
void sv_catpvn(SV* sv, const char* ptr, 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 UTF8 status set, then the bytes appended should be valid UTF8. 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* sv, const char* ptr, STRLEN len, I32 flags)
sv_catpvn_mg
Like "sv_catpvn", but also handles 'set' magic.
void sv_catpvn_mg(SV *sv, const char *ptr, STRLEN len)
sv_catpv_mg
Like "sv_catpv", but also handles 'set' magic.
void sv_catpv_mg(SV *sv, const char *ptr)
sv_catsv
Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". Modifies "dsv" but not "ssv". Handles 'get' magic,
but not 'set' magic. See "sv_catsv_mg".
void sv_catsv(SV* dsv, SV* ssv)
sv_catsv_flags
Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". Modifies "dsv" but not "ssv". If "flags" has
"SV_GMAGIC" bit set, will "mg_get" on the SVs if appropriate, else not. "sv_catsv" and "sv_catsv_nomg" are implemented in terms of
this function.
void sv_catsv_flags(SV* dsv, SV* ssv, I32 flags)
sv_catsv_mg
Like "sv_catsv", but also handles 'set' magic.
void sv_catsv_mg(SV *dstr, SV *sstr)
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".
void sv_chop(SV* sv, char* ptr)
sv_clear
Clear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV's head is not freed,
although its type is set to all 1's so that it won't inadvertently be assumed to be live during global destruction etc. This func-
tion should only be called when REFCNT is zero. Most of the time you'll want to call "sv_free()" (or its macro wrapper "SvRE-
FCNT_dec") instead.
void sv_clear(SV* sv)
sv_cmp Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in "sv1" is less than, equal to, or greater
than the string in "sv2". Is UTF-8 and 'use bytes' aware, handles get magic, and will coerce its args to strings if necessary. See
also "sv_cmp_locale".
I32 sv_cmp(SV* sv1, SV* sv2)
sv_cmp_locale
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and 'use bytes' aware, handles get magic, and will coerce its
args to strings if necessary. See also "sv_cmp_locale". See also "sv_cmp".
I32 sv_cmp_locale(SV* sv1, SV* sv2)
sv_collxfrm
Add Collate Transform magic to an SV if it doesn't already have it.
Any scalar variable may carry PERL_MAGIC_collxfrm magic that contains the scalar data of the variable, but transformed to such a
format that a normal memory comparison can be used to compare the data according to the locale settings.
char* sv_collxfrm(SV* sv, STRLEN* nxp)
sv_copypv
Copies a stringified representation of the source SV into the destination SV. Automatically performs any necessary mg_get and
coercion of numeric values into strings. Guaranteed to preserve UTF-8 flag even from overloaded objects. Similar in nature to
sv_2pv[_flags] but operates directly on an SV instead of just the string. Mostly uses sv_2pv_flags to do its work, except when
that would lose the UTF-8'ness of the PV.
void sv_copypv(SV* dsv, SV* ssv)
sv_dec Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic.
void sv_dec(SV* sv)
sv_derived_from
Returns a boolean indicating whether the SV is derived from the specified class. This is the function that implements "UNIVER-
SAL::isa". It works for class names as well as for objects.
bool sv_derived_from(SV* sv, const char* name)
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
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_force_normal_flags
Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a
glob, downgrade to an xpvmg. The "flags" parameter gets passed to "sv_unref_flags()" when unrefing. "sv_force_normal" calls this
function with flags set to 0.
void sv_force_normal_flags(SV *sv, U32 flags)
sv_free Decrement an SV's reference count, and if it drops to zero, call "sv_clear" to invoke destructors and free up any memory used by
the body; finally, deallocate the SV's head itself. Normally called via a wrapper macro "SvREFCNT_dec".
void sv_free(SV* sv)
sv_gets Get a line from the filehandle and store it into the SV, optionally appending to the currently-stored string.
char* sv_gets(SV* sv, PerlIO* fp, I32 append)
sv_grow Expands the character buffer in the SV. If necessary, uses "sv_unref" and upgrades the SV to "SVt_PV". Returns a pointer to the
character buffer. Use the "SvGROW" wrapper instead.
char* sv_grow(SV* sv, STRLEN newlen)
sv_inc Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic.
void sv_inc(SV* sv)
sv_insert
Inserts a string at the specified offset/length within the SV. Similar to the Perl substr() function.
void sv_insert(SV* bigsv, STRLEN offset, STRLEN len, char* little, STRLEN littlelen)
sv_isa Returns a boolean indicating whether the SV is blessed into the specified class. This does not check for subtypes; use
"sv_derived_from" to verify an inheritance relationship.
int sv_isa(SV* sv, const char* name)
sv_isobject
Returns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is not an RV, or if the object is not
blessed, then this will return false.
int sv_isobject(SV* sv)
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_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* sv)
sv_len_utf8
Returns the number of characters in the string in an SV, counting wide UTF8 bytes as a single character. Handles magic and type
coercion.
STRLEN sv_len_utf8(SV* 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.
void sv_magic(SV* sv, SV* obj, int how, const char* name, I32 namlen)
sv_magicext
Adds magic to an SV, upgrading it if necessary. Applies the supplied vtable and returns pointer to the magic added.
Note that sv_magicext will allow things that sv_magic will not. In particular you can add magic to SvREADONLY SVs and and more
than one instance of the same 'how'
I "namelen" is greater then zero then a savepvn() copy of "name" is stored, if "namelen" is zero then "name" is stored as-is and -
as another special case - if "(name && namelen == HEf_SVKEY)" then "name" is assumed to contain an "SV*" and has its REFCNT incre-
mented
(This is now used as a subroutine by sv_magic.)
MAGIC * sv_magicext(SV* sv, SV* obj, int how, MGVTBL *vtbl, const char* name, 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_new-
mortal" and "sv_2mortal".
SV* sv_mortalcopy(SV* 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_2mor-
tal".
SV* sv_newmortal()
sv_newref
Increment an SV's reference count. Use the "SvREFCNT_inc()" wrapper instead.
SV* sv_newref(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.
void sv_nolocking(SV *)
sv_nosharing
Dummy routine which "shares" an SV when there is no sharing module present. 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_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.
void sv_nounlocking(SV *)
sv_nv A private implementation of the "SvNVx" macro for compilers which can't cope with complex macro expressions. Always use the macro
instead.
NV sv_nv(SV* sv)
sv_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
UTF8 chars. Handles magic and type coercion.
void sv_pos_b2u(SV* sv, I32* offsetp)
sv_pos_u2b
Converts the value pointed to by offsetp from a count of UTF8 chars from the start of the string, to a count of the equivalent num-
ber 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.
void sv_pos_u2b(SV* sv, I32* offsetp, I32* lenp)
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 *len)
sv_pvbyten_force
A private implementation of the "SvPVbytex_force" macro for compilers which can't cope with complex macro expressions. Always use
the macro instead.
char* sv_pvbyten_force(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 *len)
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* sv, STRLEN* lp, I32 flags)
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 *len)
sv_pvutf8n_force
A private implementation of the "SvPVutf8_force" macro for compilers which can't cope with complex macro expressions. Always use
the macro instead.
char* sv_pvutf8n_force(SV* sv, STRLEN* lp)
sv_reftype
Returns a string describing what the SV is a reference to.
char* sv_reftype(SV* sv, 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* sv, SV* nsv)
sv_report_used
Dump the contents of all SVs not yet freed. (Debugging aid).
void sv_report_used()
sv_reset
Underlying implementation for the "reset" Perl function. Note that the perl-level function is vaguely deprecated.
void sv_reset(char* s, HV* 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.
SV* sv_rvweaken(SV *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* sv, IV num)
sv_setiv_mg
Like "sv_setiv", but also handles 'set' magic.
void sv_setiv_mg(SV *sv, IV i)
sv_setnv
Copies a double into the given SV, upgrading first if necessary. Does not handle 'set' magic. See also "sv_setnv_mg".
void sv_setnv(SV* sv, NV num)
sv_setnv_mg
Like "sv_setnv", but also handles 'set' magic.
void sv_setnv_mg(SV *sv, 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* sv, const char* ptr)
sv_setpvf
Processes its arguments like "sprintf" and sets an SV to the formatted output. Does not handle 'set' magic. See "sv_setpvf_mg".
void sv_setpvf(SV* sv, const char* pat, ...)
sv_setpvf_mg
Like "sv_setpvf", but also handles 'set' magic.
void sv_setpvf_mg(SV *sv, const char* pat, ...)
sv_setpvn
Copies a string into an SV. The "len" parameter indicates the number of bytes to be copied. Does not handle 'set' magic. See
"sv_setpvn_mg".
void sv_setpvn(SV* sv, const char* ptr, STRLEN len)
sv_setpvn_mg
Like "sv_setpvn", but also handles 'set' magic.
void sv_setpvn_mg(SV *sv, const char *ptr, STRLEN len)
sv_setpv_mg
Like "sv_setpv", but also handles 'set' magic.
void sv_setpv_mg(SV *sv, const char *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 modi-
fied to point to the new SV. The "classname" argument indicates the package for the blessing. Set "classname" to "Nullch" to
avoid the blessing. The new SV will be returned and will have a reference count of 1.
SV* sv_setref_iv(SV* rv, const char* classname, 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 "Nullch" to avoid the
blessing. The new SV will be returned and will have a reference count of 1.
SV* sv_setref_nv(SV* rv, const char* classname, 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 "Nullch" to avoid the blessing. The new SV will be returned and will
have a reference count of 1.
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.
SV* sv_setref_pv(SV* rv, const char* classname, void* 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 "Nullch" to avoid the blessing. The new SV will be returned and will have a reference count of
1.
Note that "sv_setref_pv" copies the pointer while this copies the string.
SV* sv_setref_pvn(SV* rv, const char* classname, char* pv, 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 "Nullch"
to avoid the blessing. The new SV will be returned and will have a reference count of 1.
SV* sv_setref_uv(SV* rv, const char* classname, 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 "SvSetMag-
icSV_nosteal".
void sv_setsv(SV* dsv, SV* ssv)
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" on "ssv"
if appropriate, else not. "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 "SvSetMag-
icSV_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* dsv, SV* ssv, I32 flags)
sv_setsv_mg
Like "sv_setsv", but also handles 'set' magic.
void sv_setsv_mg(SV *dstr, SV *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* sv, UV num)
sv_setuv_mg
Like "sv_setuv", but also handles 'set' magic.
void sv_setuv_mg(SV *sv, UV u)
sv_taint
Taint an SV. Use "SvTAINTED_on" instead. void sv_taint(SV* sv)
sv_tainted
Test an SV for taintedness. Use "SvTAINTED" instead. bool sv_tainted(SV* 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 *sv)
sv_unmagic
Removes all magic of type "type" from an SV.
int sv_unmagic(SV* sv, int type)
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_unref_flags
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". 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* sv, U32 flags)
sv_untaint
Untaint an SV. Use "SvTAINTED_off" instead. void sv_untaint(SV* 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".
bool sv_upgrade(SV* sv, U32 mt)
sv_usepvn
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.
This function will realloc the memory pointed to by "ptr", so that pointer should not be freed or used by the programmer after giv-
ing it to sv_usepvn. Does not handle 'set' magic. See "sv_usepvn_mg".
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_utf8_decode
Convert the octets in the PV from UTF-8 to chars. Scan for validity and then turn off SvUTF8 if needed so that we see characters.
Used as a building block for decode_utf8 in Encode.xs
NOTE: this function is experimental and may change or be removed without notice.
bool sv_utf8_decode(SV *sv)
sv_utf8_downgrade
Attempt to convert the PV of an SV from UTF8-encoded to byte encoding. This may not be possible if the PV contains non-byte encod-
ing characters; if this is the 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 *sv, bool fail_ok)
sv_utf8_encode
Convert the PV of an SV to UTF8-encoded, but then turn off the "SvUTF8" flag so that it looks like octets again. Used as a building
block for encode_utf8 in Encode.xs
void sv_utf8_encode(SV *sv)
sv_utf8_upgrade
Convert the PV of an SV to its UTF8-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 have hibit clear.
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
Convert the PV of an SV to its UTF8-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 have hibit clear. If "flags" has "SV_GMAGIC" bit set, will "mg_get" on "sv"
if appropriate, else not. "sv_utf8_upgrade" 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 *sv, I32 flags)
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)
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 untrustwor-
thy (often due to the use of locales).
Usually used via one of its frontends "sv_catpvf" and "sv_catpvf_mg".
void sv_vcatpvfn(SV* sv, const char* pat, STRLEN patlen, va_list* args, SV** svargs, I32 svmax, bool *maybe_tainted)
sv_vsetpvfn
Works like "vcatpvfn" but copies the text into the SV instead of appending it.
Usually used via one of its frontends "sv_setpvf" and "sv_setpvf_mg".
void sv_vsetpvfn(SV* sv, const char* pat, STRLEN patlen, va_list* args, SV** svargs, I32 svmax, bool *maybe_tainted)
Unicode Support
bytes_from_utf8
Converts a string "s" of length "len" from UTF8 into 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 contains all 7bit char-
acters.
NOTE: this function is experimental and may change or be removed without notice.
U8* bytes_from_utf8(U8 *s, STRLEN *len, bool *is_utf8)
bytes_to_utf8
Converts a string "s" of length "len" from ASCII into UTF8 encoding. Returns a pointer to the newly-created string, and sets "len"
to reflect the new length.
NOTE: this function is experimental and may change or be removed without notice.
U8* bytes_to_utf8(U8 *s, STRLEN *len)
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 Uni-
code. 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 char-
acter). If the pointers behind pe1 or pe2 are non-NULL, they are the end pointers beyond which scanning will not continue under
any circustances. 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* a, char **pe1, UV l1, bool u1, const char* b, char **pe2, UV l2, bool u2)
is_utf8_char
Tests if some arbitrary number of bytes begins in a valid UTF-8 character. Note that an INVARIANT (i.e. ASCII) 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(U8 *p)
is_utf8_string
Returns true if first "len" bytes of the given string form a valid UTF8 string, false otherwise. Note that 'a valid UTF8 string'
does not mean 'a string that contains UTF8' because a valid ASCII string is a valid UTF8 string.
bool is_utf8_string(U8 *s, STRLEN len)
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 '
') (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.
char* pv_uni_display(SV *dsv, U8 *spv, STRLEN len, STRLEN pvlim, UV flags)
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 encod-
ing 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 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 SWASHGET, using lib/utf8_heavy.pl. The spe-
cial (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(U8 *p, U8* ustrp, STRLEN *lenp, SV **swash, char *normal, 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_MAXLEN_FOLD+1 bytes since the foldcase version may be longer than the original char-
acter (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(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_MAXLEN_UCLC+1 bytes since the lowercase version may be longer than the original char-
acter (up to two characters).
The first character of the lowercased version is returned (but note, as explained above, that there may be more.)
UV to_utf8_lower(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_MAXLEN_UCLC+1 bytes since the titlecase version may be longer than the original char-
acter (up to two characters).
The first character of the titlecased version is returned (but note, as explained above, that there may be more.)
UV to_utf8_title(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_MAXLEN_UCLC+1 bytes since the uppercase version may be longer than the original char-
acter (up to two characters).
The first character of the uppercased version is returned (but note, as explained above, that there may be more.)
UV to_utf8_upper(U8 *p, U8* ustrp, STRLEN *lenp)
utf8n_to_uvchr
Returns the native character value of the first character in the string "s" which is assumed to be in UTF8 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(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 UTF8 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 UTF8 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, 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(U8 *s, STRLEN curlen, STRLEN* retlen, U32 flags)
utf8_distance
Returns the number of UTF8 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(U8 *a, 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(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(U8* s, U8 *e)
utf8_to_bytes
Converts a string "s" of length "len" from UTF8 into 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.
NOTE: this function is experimental and may change or be removed without notice.
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 UTF8 encoding; "retlen" will
be set to the length, in bytes, of that character.
If "s" does not point to a well-formed UTF8 character, zero is returned and retlen is set, if possible, to -1.
UV utf8_to_uvchr(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 UTF8 encoding; "retlen" will be
set to the length, in bytes, of that character.
This function should only be used when returned UV is considered an index into the Unicode semantic tables (e.g. swashes).
If "s" does not point to a well-formed UTF8 character, zero is returned and retlen is set, if possible, to -1.
UV utf8_to_uvuni(U8 *s, STRLEN* retlen)
uvchr_to_utf8
Adds the UTF8 representation of the Native codepoint "uv" to the end of the string "d"; "d" should be have at least "UTF8_MAXLEN+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 UTF8 representation of the Unicode codepoint "uv" to the end of the string "d"; "d" should be have at least
"UTF8_MAXLEN+1" free bytes available. The return value is the pointer to the 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;
dITEMS Sets up the "items" variable. This is usually handled automatically by "xsubpp" by calling "dXSARGS".
dITEMS;
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 per-
lxs.
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
XS Macro to declare an XSUB and its C parameter list. This is handled by "xsubpp".
XSRETURN_EMPTY
Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;
XS_VERSION
The version identifier for an XS module. This is usually handled automatically by "ExtUtils::MakeMaker". See "XS_VER-
SION_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 auto-
matically 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 use this function the same way you use the C "printf" func-
tion. See "warn".
If you want to throw an exception object, assign the object to $@ and then pass "Nullch" to croak():
errsv = get_sv("@", TRUE);
sv_setsv(errsv, exception_object);
croak(Nullch);
void croak(const char* pat, ...)
warn This is the XSUB-writer's interface to Perl's "warn" function. Use this function the same way you use the C "printf" function.
See "croak".
void warn(const char* pat, ...)
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.
SEE ALSO
perlguts(1), perlxs(1), perlxstut(1), perlintern(1)
perl v5.8.0 2003-02-18 PERLAPI(1)