X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/3fe9a6f19eb206c685bd7389e54e2838fdfd04b7..54fbcc6e8ef8d379545ca2bc110f2f19a7c73715:/pod/perlguts.pod diff --git a/pod/perlguts.pod b/pod/perlguts.pod index ff3d6cd..769fd01 100644 --- a/pod/perlguts.pod +++ b/pod/perlguts.pod @@ -28,36 +28,56 @@ guaranteed to be large enough to hold a pointer (as well as an integer). Perl also uses two special typedefs, I32 and I16, which will always be at least 32-bits and 16-bits long, respectively. -=head2 Working with SV's +=head2 Working with SVs An SV can be created and loaded with one command. There are four types of values that can be loaded: an integer value (IV), a double (NV), a string, (PV), and another scalar (SV). -The four routines are: +The six routines are: SV* newSViv(IV); SV* newSVnv(double); SV* newSVpv(char*, int); + SV* newSVpvn(char*, int); + SV* newSVpvf(const char*, ...); SV* newSVsv(SV*); -To change the value of an *already-existing* SV, there are five routines: +To change the value of an *already-existing* SV, there are seven routines: void sv_setiv(SV*, IV); + void sv_setuv(SV*, UV); void sv_setnv(SV*, double); - void sv_setpvn(SV*, char*, int) void sv_setpv(SV*, char*); + void sv_setpvn(SV*, char*, int) + void sv_setpvf(SV*, const char*, ...); + void sv_setpvfn(SV*, const char*, STRLEN, va_list *, SV **, I32, bool); void sv_setsv(SV*, SV*); Notice that you can choose to specify the length of the string to be -assigned by using C or C, or you may allow Perl to -calculate the length by using C or by specifying 0 as the second -argument to C. Be warned, though, that Perl will determine the -string's length by using C, which depends on the string terminating -with a NUL character. - -All SV's that will contain strings should, but need not, be terminated -with a NUL character. If it is not NUL-terminated there is a risk of +assigned by using C, C, or C, or you may +allow Perl to calculate the length by using C or by specifying +0 as the second argument to C. Be warned, though, that Perl will +determine the string's length by using C, which depends on the +string terminating with a NUL character. + +The arguments of C are processed like C, and the +formatted output becomes the value. + +C is an analogue of C, but it allows you to specify +either a pointer to a variable argument list or the address and length of +an array of SVs. The last argument points to a boolean; on return, if that +boolean is true, then locale-specific information has been used to format +the string, and the string's contents are therefore untrustworty (see +L). This pointer may be NULL if that information is not +important. Note that this function requires you to specify the length of +the format. + +The C functions are not generic enough to operate on values +that have "magic". See L later in this document. + +All SVs that contain strings should be terminated with a NUL character. +If it is not NUL-terminated there is a risk of core dumps and corruptions from code which passes the string to C functions or system calls which expect a NUL-terminated string. Perl's own functions typically add a trailing NUL for this reason. @@ -75,9 +95,9 @@ or string. In the C macro, the length of the string returned is placed into the variable C (this is a macro, so you do I use C<&len>). If you do not -care what the length of the data is, use the global variable C. Remember, +care what the length of the data is, use the global variable C. Remember, however, that Perl allows arbitrary strings of data that may both contain -NUL's and might not be terminated by a NUL. +NULs and might not be terminated by a NUL. If you want to know if the scalar value is TRUE, you can use: @@ -119,13 +139,21 @@ you can use the following functions: void sv_catpv(SV*, char*); void sv_catpvn(SV*, char*, int); + void sv_catpvf(SV*, const char*, ...); + void sv_catpvfn(SV*, const char*, STRLEN, va_list *, SV **, I32, bool); void sv_catsv(SV*, SV*); The first function calculates the length of the string to be appended by using C. In the second, you specify the length of the string -yourself. The third function extends the string stored in the first SV -with the string stored in the second SV. It also forces the second SV to -be interpreted as a string. +yourself. The third function processes its arguments like C and +appends the formatted output. The fourth function works like C. +You can specify the address and length of an array of SVs instead of the +va_list argument. The fifth function extends the string stored in the first +SV with the string stored in the second SV. It also forces the second SV +to be interpreted as a string. + +The C functions are not generic enough to operate on values that +have "magic". See L later in this document. If you know the name of a scalar variable, you can get a pointer to its SV by using the following: @@ -139,14 +167,14 @@ you can call: SvOK(SV*) -The scalar C value is stored in an SV instance called C. Its +The scalar C value is stored in an SV instance called C. Its address can be used whenever an C is needed. -There are also the two values C and C, which contain Boolean -TRUE and FALSE values, respectively. Like C, their addresses can +There are also the two values C and C, which contain Boolean +TRUE and FALSE values, respectively. Like C, their addresses can be used whenever an C is needed. -Do not be fooled into thinking that C<(SV *) 0> is the same as C<&sv_undef>. +Do not be fooled into thinking that C<(SV *) 0> is the same as C<&PL_sv_undef>. Take this code: SV* sv = (SV*) 0; @@ -156,9 +184,9 @@ Take this code: sv_setsv(ST(0), sv); This code tries to return a new SV (which contains the value 42) if it should -return a real value, or undef otherwise. Instead it has returned a null +return a real value, or undef otherwise. Instead it has returned a NULL pointer which, somewhere down the line, will cause a segmentation violation, -bus error, or just weird results. Change the zero to C<&sv_undef> in the first +bus error, or just weird results. Change the zero to C<&PL_sv_undef> in the first line and all will be well. To free an SV that you've created, call C. Normally this @@ -184,21 +212,21 @@ stored in your SV. The "p" stands for private. In general, though, it's best to use the C macros. -=head2 Working with AV's +=head2 Working with AVs There are two ways to create and load an AV. The first method creates an empty AV: AV* newAV(); -The second method both creates the AV and initially populates it with SV's: +The second method both creates the AV and initially populates it with SVs: AV* av_make(I32 num, SV **ptr); The second argument points to an array containing C C's. Once the -AV has been created, the SV's can be destroyed, if so desired. +AV has been created, the SVs can be destroyed, if so desired. -Once the AV has been created, the following operations are possible on AV's: +Once the AV has been created, the following operations are possible on AVs: void av_push(AV*, SV*); SV* av_pop(AV*); @@ -220,9 +248,12 @@ The C function returns the highest index value in array (just like $#array in Perl). If the array is empty, -1 is returned. The C function returns the value at index C, but if C is non-zero, then C will store an undef value at that index. -The C function stores the value C at index C. -note that C and C both return C's, not C's -as their return value. +The C function stores the value C at index C, and does +not increment the reference count of C. Thus the caller is responsible +for taking care of that, and if C returns NULL, the caller will +have to decrement the reference count to avoid a memory leak. Note that +C and C both return C's, not C's as their +return value. void av_clear(AV*); void av_undef(AV*); @@ -242,13 +273,16 @@ by using the following: This returns NULL if the variable does not exist. -=head2 Working with HV's +See L for more +information on how to use the array access functions on tied arrays. + +=head2 Working with HVs To create an HV, you use the following routine: HV* newHV(); -Once the HV has been created, the following operations are possible on HV's: +Once the HV has been created, the following operations are possible on HVs: SV** hv_store(HV*, char* key, U32 klen, SV* val, U32 hash); SV** hv_fetch(HV*, char* key, U32 klen, I32 lval); @@ -256,7 +290,7 @@ Once the HV has been created, the following operations are possible on HV's: The C parameter is the length of the key being passed in (Note that you cannot pass 0 in as a value of C to tell Perl to measure the length of the key). The C argument contains the SV pointer to the -scalar being stored, and C is the pre-computed hash value (zero if +scalar being stored, and C is the precomputed hash value (zero if you want C to calculate it for you). The C parameter indicates whether this fetch is actually a part of a store operation, in which case a new undefined value will be added to the HV with the supplied @@ -322,6 +356,9 @@ The hash algorithm is defined in the C macro: while (i--) hash = hash * 33 + *s++; +See L for more +information on how to use the hash access functions on tied hashes. + =head2 Hash API Extensions Beginning with version 5.004, the following functions are also supported: @@ -363,6 +400,10 @@ dealing with keys that are not Cs: HeKEY(HE* he) HeKLEN(HE* he) +Note that both C and C do not increment the +reference count of the stored C, which is the caller's responsibility. +If these functions return a NULL value, the caller will usually have to +decrement the reference count of C to avoid a memory leak. =head2 References @@ -449,8 +490,25 @@ Perl calculate the string length. SV is blessed if C is non-null. SV* sv_setref_pvn(SV* rv, char* classname, PV iv, int length); - int sv_isa(SV* sv, char* name); - int sv_isobject(SV* sv); +Tests whether the SV is blessed into the specified class. It does not +check inheritance relationships. + + int sv_isa(SV* sv, char* name); + +Tests whether the SV is a reference to a blessed object. + + int sv_isobject(SV* sv); + +Tests whether the SV is derived from the specified class. SV can be either +a reference to a blessed object or a string containing a class name. This +is the function implementing the C functionality. + + bool sv_derived_from(SV* sv, char* name); + +To check if you've got an object derived from a specific class you have +to write: + + if (sv_isobject(sv) && sv_derived_from(sv, class)) { ... } =head2 Creating New Variables @@ -468,7 +526,7 @@ There are additional macros whose values may be bitwise OR'ed with the C argument to enable certain extra features. Those bits are: GV_ADDMULTI Marks the variable as multiply defined, thus preventing the - "Indentifier used only once: possible typo" warning. + "Name used only once: possible typo" warning. GV_ADDWARN Issues the warning "Had to create unexpectedly" if the variable did not exist before the function was called. @@ -477,8 +535,8 @@ package. =head2 Reference Counts and Mortality -Perl uses an reference count-driven garbage collection mechanism. SV's, -AV's, or HV's (xV for short in the following) start their life with a +Perl uses an reference count-driven garbage collection mechanism. SVs, +AVs, or HVs (xV for short in the following) start their life with a reference count of 1. If the reference count of an xV ever drops to 0, then it will be destroyed and its memory made available for reuse. @@ -514,11 +572,11 @@ the reference count of the SV will go to zero and it will be destroyed, stopping any memory leak. There are some convenience functions available that can help with the -destruction of xV's. These functions introduce the concept of "mortality". +destruction of xVs. These functions introduce the concept of "mortality". An xV that is mortal has had its reference count marked to be decremented, but not actually decremented, until "a short time later". Generally the term "short time later" means a single Perl statement, such as a call to -an XSUB function. The actual determinant for when mortal xV's have their +an XSUB function. The actual determinant for when mortal xVs have their reference count decremented depends on two macros, SAVETMPS and FREETMPS. See L and L for more details on these macros. @@ -540,7 +598,7 @@ The first call creates a mortal SV, the second converts an existing SV to a mortal SV (and thus defers a call to C), and the third creates a mortal copy of an existing SV. -The mortal routines are not just for SV's -- AV's and HV's can be +The mortal routines are not just for SVs -- AVs and HVs can be made mortal by passing their address (type-casted to C) to the C or C routines. @@ -556,15 +614,14 @@ including (but not limited to) the following: Scalar Value Array Value Hash Value - File Handle - Directory Handle + I/O Handle Format Subroutine -There is a single stash called "defstash" that holds the items that exist +There is a single stash called "PL_defstash" that holds the items that exist in the "main" package. To get at the items in other packages, append the string "::" to the package name. The items in the "Foo" package are in -the stash "Foo::" in defstash. The items in the "Bar::Baz" package are +the stash "Foo::" in PL_defstash. The items in the "Bar::Baz" package are in the stash "Baz::" in "Bar::"'s stash. To get the stash pointer for a particular package, use the function: @@ -601,7 +658,7 @@ as any other SV. For more information on references and blessings, consult L. -=head2 Double-Typed SV's +=head2 Double-Typed SVs Scalar variables normally contain only one type of value, an integer, double, pointer, or reference. Perl will automatically convert the @@ -679,9 +736,9 @@ entry of the same type of magic is deleted. Note that this can be overridden, and multiple instances of the same type of magic can be associated with an SV. -The C and C arguments are used to associate a string with -the magic, typically the name of a variable. C is stored in the -C field and if C is non-null and C >= 0 a malloc'd +The C and C arguments are used to associate a string with +the magic, typically the name of a variable. C is stored in the +C field and if C is non-null and C >= 0 a malloc'd copy of the name is stored in C field. The sv_magic function uses C to determine which, if any, predefined @@ -692,7 +749,7 @@ stored in the C field. The C argument is stored in the C field of the C structure. If it is not the same as the C argument, the reference count of the C object is incremented. If it is the same, or if -the C argument is "#", or if it is a null pointer, then C is +the C argument is "#", or if it is a NULL pointer, then C is merely stored, without the reference count being incremented. There is also a function to add magic to an C: @@ -747,52 +804,96 @@ the various routines for the various magical types begin with C. The current kinds of Magic Virtual Tables are: - mg_type MGVTBL Type of magical + mg_type MGVTBL Type of magic ------- ------ ---------------------------- - \0 vtbl_sv Regexp??? - A vtbl_amagic Operator Overloading - a vtbl_amagicelem Operator Overloading - c 0 Used in Operator Overloading - B vtbl_bm Boyer-Moore??? + \0 vtbl_sv Special scalar variable + A vtbl_amagic %OVERLOAD hash + a vtbl_amagicelem %OVERLOAD hash element + c (none) Holds overload table (AMT) on stash + B vtbl_bm Boyer-Moore (fast string search) E vtbl_env %ENV hash e vtbl_envelem %ENV hash element - g vtbl_mglob Regexp /g flag??? + f vtbl_fm Formline ('compiled' format) + g vtbl_mglob m//g target / study()ed string I vtbl_isa @ISA array i vtbl_isaelem @ISA array element - L 0 (but sets RMAGICAL) Perl Module/Debugger??? - l vtbl_dbline Debugger? + k vtbl_nkeys scalar(keys()) lvalue + L (none) Debugger %_'s +C field points to a C structure: + + struct ufuncs { + I32 (*uf_val)(IV, SV*); + I32 (*uf_set)(IV, SV*); + IV uf_index; + }; -Note that because multiple extensions may be using ~ magic it is -important for extensions to take extra care with it. Typically only -using it on objects blessed into the same class as the extension -is sufficient. It may also be appropriate to add an I32 'signature' -at the top of the private data area and check that. +When the SV is read from or written to, the C or C +function will be called with C as the first arg and a +pointer to the SV as the second. A simple example of how to add 'U' +magic is shown below. Note that the ufuncs structure is copied by +sv_magic, so you can safely allocate it on the stack. + + void + Umagic(sv) + SV *sv; + PREINIT: + struct ufuncs uf; + CODE: + uf.uf_val = &my_get_fn; + uf.uf_set = &my_set_fn; + uf.uf_index = 0; + sv_magic(sv, 0, 'U', (char*)&uf, sizeof(uf)); + +Note that because multiple extensions may be using '~' or 'U' magic, +it is important for extensions to take extra care to avoid conflict. +Typically only using the magic on objects blessed into the same class +as the extension is sufficient. For '~' magic, it may also be +appropriate to add an I32 'signature' at the top of the private data +area and check that. + +Also note that the C and C functions described +earlier do B invoke 'set' magic on their targets. This must +be done by the user either by calling the C macro after +calling these functions, or by using one of the C or +C functions. Similarly, generic C code must call the +C macro to invoke any 'get' magic if they use an SV +obtained from external sources in functions that don't handle magic. +L later in this document identifies such functions. +For example, calls to the C functions typically need to be +followed by C, but they don't need a prior C +since their implementation handles 'get' magic. =head2 Finding Magic @@ -800,7 +901,7 @@ at the top of the private data area and check that. This routine returns a pointer to the C structure stored in the SV. If the SV does not have that magical feature, C is returned. Also, -if the SV is not of type SVt_PVMG, Perl may core-dump. +if the SV is not of type SVt_PVMG, Perl may core dump. int mg_copy(SV* sv, SV* nsv, char* key, STRLEN klen); @@ -808,6 +909,236 @@ This routine checks to see what types of magic C has. If the mg_type field is an uppercase letter, then the mg_obj is copied to C, but the mg_type field is changed to be the lowercase letter. +=head2 Understanding the Magic of Tied Hashes and Arrays + +Tied hashes and arrays are magical beasts of the 'P' magic type. + +WARNING: As of the 5.004 release, proper usage of the array and hash +access functions requires understanding a few caveats. Some +of these caveats are actually considered bugs in the API, to be fixed +in later releases, and are bracketed with [MAYCHANGE] below. If +you find yourself actually applying such information in this section, be +aware that the behavior may change in the future, umm, without warning. + +The perl tie function associates a variable with an object that implements +the various GET, SET etc methods. To perform the equivalent of the perl +tie function from an XSUB, you must mimic this behaviour. The code below +carries out the necessary steps - firstly it creates a new hash, and then +creates a second hash which it blesses into the class which will implement +the tie methods. Lastly it ties the two hashes together, and returns a +reference to the new tied hash. Note that the code below does NOT call the +TIEHASH method in the MyTie class - +see L for details on how +to do this. + + SV* + mytie() + PREINIT: + HV *hash; + HV *stash; + SV *tie; + CODE: + hash = newHV(); + tie = newRV_noinc((SV*)newHV()); + stash = gv_stashpv("MyTie", TRUE); + sv_bless(tie, stash); + hv_magic(hash, tie, 'P'); + RETVAL = newRV_noinc(hash); + OUTPUT: + RETVAL + +The C function, when given a tied array argument, merely +copies the magic of the array onto the value to be "stored", using +C. It may also return NULL, indicating that the value did not +actually need to be stored in the array. [MAYCHANGE] After a call to +C on a tied array, the caller will usually need to call +C to actually invoke the perl level "STORE" method on the +TIEARRAY object. If C did return NULL, a call to +C will also be usually necessary to avoid a memory +leak. [/MAYCHANGE] + +The previous paragraph is applicable verbatim to tied hash access using the +C and C functions as well. + +C and the corresponding hash functions C and +C actually return an undefined mortal value whose magic +has been initialized using C. Note the value so returned does not +need to be deallocated, as it is already mortal. [MAYCHANGE] But you will +need to call C on the returned value in order to actually invoke +the perl level "FETCH" method on the underlying TIE object. Similarly, +you may also call C on the return value after possibly assigning +a suitable value to it using C, which will invoke the "STORE" +method on the TIE object. [/MAYCHANGE] + +[MAYCHANGE] +In other words, the array or hash fetch/store functions don't really +fetch and store actual values in the case of tied arrays and hashes. They +merely call C to attach magic to the values that were meant to be +"stored" or "fetched". Later calls to C and C actually +do the job of invoking the TIE methods on the underlying objects. Thus +the magic mechanism currently implements a kind of lazy access to arrays +and hashes. + +Currently (as of perl version 5.004), use of the hash and array access +functions requires the user to be aware of whether they are operating on +"normal" hashes and arrays, or on their tied variants. The API may be +changed to provide more transparent access to both tied and normal data +types in future versions. +[/MAYCHANGE] + +You would do well to understand that the TIEARRAY and TIEHASH interfaces +are mere sugar to invoke some perl method calls while using the uniform hash +and array syntax. The use of this sugar imposes some overhead (typically +about two to four extra opcodes per FETCH/STORE operation, in addition to +the creation of all the mortal variables required to invoke the methods). +This overhead will be comparatively small if the TIE methods are themselves +substantial, but if they are only a few statements long, the overhead +will not be insignificant. + +=head2 Localizing changes + +Perl has a very handy construction + + { + local $var = 2; + ... + } + +This construction is I equivalent to + + { + my $oldvar = $var; + $var = 2; + ... + $var = $oldvar; + } + +The biggest difference is that the first construction would +reinstate the initial value of $var, irrespective of how control exits +the block: C, C, C/C etc. It is a little bit +more efficient as well. + +There is a way to achieve a similar task from C via Perl API: create a +I, and arrange for some changes to be automatically +undone at the end of it, either explicit, or via a non-local exit (via +die()). A I-like construct is created by a pair of +C/C macros (see L). Such a construct may be created specially for some +important localized task, or an existing one (like boundaries of +enclosing Perl subroutine/block, or an existing pair for freeing TMPs) +may be used. (In the second case the overhead of additional +localization must be almost negligible.) Note that any XSUB is +automatically enclosed in an C/C pair. + +Inside such a I the following service is available: + +=over + +=item C + +=item C + +=item C + +=item C + +These macros arrange things to restore the value of integer variable +C at the end of enclosing I. + +=item C + +=item C + +These macros arrange things to restore the value of pointers C and +C

. C must be a pointer of a type which survives conversion to +C and back, C

should be able to survive conversion to C +and back. + +=item C + +The refcount of C would be decremented at the end of +I. This is similar to C, which should (?) be +used instead. + +=item C + +The C is op_free()ed at the end of I. + +=item C + +The chunk of memory which is pointed to by C

is Safefree()ed at the +end of I. + +=item C + +Clears a slot in the current scratchpad which corresponds to C at +the end of I. + +=item C + +The key C of C is deleted at the end of I. The +string pointed to by C is Safefree()ed. If one has a I in +short-lived storage, the corresponding string may be reallocated like +this: + + SAVEDELETE(PL_defstash, savepv(tmpbuf), strlen(tmpbuf)); + +=item C + +At the end of I the function C is called with the +only argument (of type C) C

. + +=item C + +The current offset on the Perl internal stack (cf. C) is restored +at the end of I. + +=back + +The following API list contains functions, thus one needs to +provide pointers to the modifiable data explicitly (either C pointers, +or Perlish Cs). Where the above macros take C, a similar +function takes C. + +=over + +=item C + +Equivalent to Perl code C. + +=item C + +=item C + +Similar to C, but localize C<@gv> and C<%gv>. + +=item C + +Duplicates the current value of C, on the exit from the current +C/C I will restore the value of C +using the stored value. + +=item C + +A variant of C which takes multiple arguments via an array +C of C of length C. + +=item C + +Similar to C, but will reinstate a C. + +=item C + +=item C + +Similar to C, but localize C and C. + +=back + +The C module implements localization of the basic types within the +I. People who are interested in how to localize things in +the containing scope should take a look there too. + =head1 Subroutines =head2 XSUBs and the Argument Stack @@ -830,13 +1161,13 @@ two, the local time zone's standard and summer time abbreviations. To handle this situation, the PPCODE directive is used and the stack is extended using the macro: - EXTEND(sp, num); + EXTEND(SP, num); -where C is the stack pointer, and C is the number of elements the -stack should be extended by. +where C is the macro that represents the local copy of the stack pointer, +and C is the number of elements the stack should be extended by. Now that there is room on the stack, values can be pushed on it using the -macros to push IV's, doubles, strings, and SV pointers respectively: +macros to push IVs, doubles, strings, and SV pointers respectively: PUSHi(IV) PUSHn(double) @@ -886,6 +1217,7 @@ must manipulate the Perl stack. These include the following macros and functions: dSP + SP PUSHMARK() PUTBACK SPAGAIN @@ -979,20 +1311,20 @@ others, which use it via C<(X)PUSH[pni]>. =head2 Scratchpads -The question remains on when the SV's which are Is for opcodes +The question remains on when the SVs which are Is for opcodes are created. The answer is that they are created when the current unit -- a subroutine or a file (for opcodes for statements outside of subroutines) -- is compiled. During this time a special anonymous Perl array is created, which is called a scratchpad for the current unit. -A scratchpad keeps SV's which are lexicals for the current unit and are +A scratchpad keeps SVs which are lexicals for the current unit and are targets for opcodes. One can deduce that an SV lives on a scratchpad by looking on its flags: lexicals have C set, and Is have C set. -The correspondence between OP's and Is is not 1-to-1. Different -OP's in the compile tree of the unit can use the same target, if this +The correspondence between OPs and Is is not 1-to-1. Different +OPs in the compile tree of the unit can use the same target, if this would not conflict with the expected life of the temporary. =head2 Scratchpads and recursion @@ -1034,7 +1366,7 @@ This is converted to a tree similar to this one: / \ $b $c -(but slightly more complicated). This tree reflect the way Perl +(but slightly more complicated). This tree reflects the way Perl parsed your code, but has nothing to do with the execution order. There is an additional "thread" going through the nodes of the tree which shows the order of execution of the nodes. In our simplified @@ -1107,7 +1439,7 @@ and corresponding check routines is described in F (do not forget to run C if you modify this file). A check routine is called when the node is fully constructed except -for the execution-order thread. Since at this time there is no +for the execution-order thread. Since at this time there are no back-links to the currently constructed node, one can do most any operation to the top-level node, including freeing it and/or creating new nodes above/below it. @@ -1134,7 +1466,7 @@ created. =head2 Compile pass 2: context propagation When a context for a part of compile tree is known, it is propagated -down through the tree. Aat this time the context can have 5 values +down through the tree. At this time the context can have 5 values (instead of 2 for runtime context): void, boolean, scalar, list, and lvalue. In contrast with the pass 1 this pass is processed from top to bottom: a node's context determines the context for its children. @@ -1150,7 +1482,7 @@ of free()ing (i.e. their type is changed to OP_NULL). After the compile tree for a subroutine (or for an C or a file) is created, an additional pass over the code is performed. This pass is neither top-down or bottom-up, but in the execution order (with -additional compilications for conditionals). These optimizations are +additional complications for conditionals). These optimizations are done in the subroutine peep(). Optimizations performed at this stage are subject to the same restrictions as in the pass 2. @@ -1160,24 +1492,31 @@ This is a listing of functions, macros, flags, and variables that may be useful to extension writers or that may be found while reading other extensions. -=over 8 +Note that all Perl API global variables must be referenced with the C +prefix. Some macros are provided for compatibility with the older, +unadorned names, but this support will be removed in a future release. -=item AvFILL +It is strongly recommended that all Perl API functions that don't begin +with C be referenced with an explicit C prefix. + +The sort order of the listing is case insensitive, with any +occurrences of '_' ignored for the the purpose of sorting. -See C. +=over 8 =item av_clear -Clears an array, making it empty. +Clears an array, making it empty. Does not free the memory used by the +array itself. - void av_clear _((AV* ar)); + void av_clear (AV* ar) =item av_extend Pre-extend an array. The C is the index to which the array should be extended. - void av_extend _((AV* ar, I32 key)); + void av_extend (AV* ar, I32 key) =item av_fetch @@ -1185,13 +1524,20 @@ Returns the SV at the specified index in the array. The C is the index. If C is set then the fetch will be part of a store. Check that the return value is non-null before dereferencing it to a C. - SV** av_fetch _((AV* ar, I32 key, I32 lval)); +See L for more +information on how to use this function on tied arrays. + + SV** av_fetch (AV* ar, I32 key, I32 lval) + +=item AvFILL + +Same as C. Deprecated, use C instead. =item av_len Returns the highest index in the array. Returns -1 if the array is empty. - I32 av_len _((AV* ar)); + I32 av_len (AV* ar) =item av_make @@ -1199,48 +1545,55 @@ 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* av_make (I32 size, SV** svp) =item av_pop -Pops an SV off the end of the array. Returns C<&sv_undef> if the array is +Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array is empty. - SV* av_pop _((AV* ar)); + SV* av_pop (AV* ar) =item 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)); + void av_push (AV* ar, SV* val) =item av_shift Shifts an SV off the beginning of the array. - SV* av_shift _((AV* ar)); + SV* av_shift (AV* ar) =item av_store Stores an SV in an array. The array index is specified as C. The -return value will be null if the operation failed, otherwise it can be -dereferenced to get the original C. +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 C. Note that the +caller is responsible for suitably incrementing the reference count of C +before the call, and decrementing it if the function returned NULL. - SV** av_store _((AV* ar, I32 key, SV* val)); +See L for more +information on how to use this function on tied arrays. + + SV** av_store (AV* ar, I32 key, SV* val) =item av_undef -Undefines the array. +Undefines the array. Frees the memory used by the array itself. - void av_undef _((AV* ar)); + void av_undef (AV* ar) =item av_unshift -Unshift an SV onto the beginning of the array. The array will grow -automatically to accommodate the addition. +Unshift the given number of C values onto the beginning of the +array. The array will grow automatically to accommodate the addition. +You must then use C to assign values to these new elements. - void av_unshift _((AV* ar, I32 num)); + void av_unshift (AV* ar, I32 num) =item CLASS @@ -1252,9 +1605,9 @@ L. The XSUB-writer's interface to the C C function. The C is the source, C is the destination, C is the number of items, and C is -the type. +the type. May fail on overlapping copies. See also C. - (void) Copy( s, d, n, t ); + void Copy( s, d, n, t ) =item croak @@ -1265,29 +1618,29 @@ function the same way you use the C C function. See C. Returns the stash of the CV. - HV * CvSTASH( SV* sv ) + HV* CvSTASH( SV* sv ) -=item DBsingle +=item PL_DBsingle When Perl is run in debugging mode, with the B<-d> switch, this SV is a boolean which indicates whether subs are being single-stepped. Single-stepping is automatically turned on after every step. This is the C -variable which corresponds to Perl's $DB::single variable. See C. +variable which corresponds to Perl's $DB::single variable. See C. -=item DBsub +=item PL_DBsub When Perl is run in debugging mode, with the B<-d> switch, this GV contains the SV which holds the name of the sub being debugged. This is the C -variable which corresponds to Perl's $DB::sub variable. See C. +variable which corresponds to Perl's $DB::sub variable. See C. The sub name can be found by - SvPV( GvSV( DBsub ), na ) + SvPV( GvSV( PL_DBsub ), PL_na ) -=item DBtrace +=item PL_DBtrace Trace variable used when Perl is run in debugging mode, with the B<-d> switch. This is the C variable which corresponds to Perl's $DB::trace -variable. See C. +variable. See C. =item dMARK @@ -1298,13 +1651,14 @@ C. Saves the original stack mark for the XSUB. See C. -=item dowarn +=item PL_dowarn The C variable which corresponds to Perl's $^W warning variable. =item dSP -Declares a stack pointer variable, C, for the XSUB. See C. +Declares a local copy of perl's stack pointer for the XSUB, available via +the C macro. See C. =item dXSARGS @@ -1317,10 +1671,12 @@ to indicate the number of items on the stack. Sets up the C variable for an XSUB which has aliases. This is usually handled automatically by C. -=item dXSI32 +=item do_binmode -Sets up the C variable for an XSUB which has aliases. This is usually -handled automatically by C. +Switches filehandle to binmode. C is what C would +contain. + + do_binmode(fp, iotype, TRUE); =item ENTER @@ -1332,7 +1688,23 @@ Opening bracket on a callback. See C and L. Used to extend the argument stack for an XSUB's return values. - EXTEND( sp, int x ); + EXTEND( sp, int x ) + +=item 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) + +=item fbm_instr + +Returns the location of the SV in the string delimited by C and +C. It returns C if the string can't be found. The +C does not have to be fbm_compiled, but the search will not be as +fast then. + + char* fbm_instr(char *str, char *strend, SV *sv, U32 flags) =item FREETMPS @@ -1343,7 +1715,7 @@ L. =item G_ARRAY -Used to indicate array context. See C and L. +Used to indicate array context. See C, C and L. =item G_DISCARD @@ -1356,8 +1728,14 @@ Used to force a Perl C wrapper around a callback. See L. =item GIMME -The XSUB-writer's equivalent to Perl's C. Returns C or -C for scalar or array context. +A backward-compatible version of C which can only return +C or C; in a void context, it returns C. + +=item GIMME_V + +The XSUB-writer's equivalent to Perl's C. Returns +C, C or C for void, scalar or array +context, respectively. =item G_NOARGS @@ -1365,13 +1743,13 @@ Indicates that no arguments are being sent to a callback. See L. =item G_SCALAR -Used to indicate scalar context. See C and L. +Used to indicate scalar context. See C, C, and L. =item gv_fetchmeth Returns the glob with the given C and a defined subroutine or C. The glob lives in the given C, or in the stashes -accessable via @ISA and @. +accessible via @ISA and @UNIVERSAL. The argument C should be either 0 or -1. If C, as a side-effect creates a glob with the given C in the given @@ -1386,28 +1764,41 @@ which is not visible to Perl code. So when calling C, you should not use the GV directly; instead, you should use the method's CV, which can be obtained from the GV with the C macro. - GV* gv_fetchmeth _((HV* stash, char* name, STRLEN len, I32 level)); + GV* gv_fetchmeth (HV* stash, char* name, STRLEN len, I32 level) =item gv_fetchmethod +=item gv_fetchmethod_autoload + Returns the glob which contains the subroutine to call to invoke the -method on the C. In fact in the presense of autoloading this may -be the glob for "AUTOLOAD". In this case the corresponing variable +method on the C. In fact in the presense of autoloading this may +be the glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD is already setup. -Note that if you want to keep this glob for a long time, you need to -check for it being "AUTOLOAD", since at the later time the call +The third parameter of C 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 +C is equivalent to calling C with a +non-zero C parameter. + +These functions grant C<"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. -This function grants C<"SUPER"> token as a prefix of the method name. - -Has the same side-effects and as C with C. -C should be writable if contains C<':'> or C<'\''>. +These functions have the same side-effects and as C with +C. C should be writable if contains C<':'> or C<'\''>. The warning against passing the GV returned by C to -C apply equally to C. +C apply equally to these functions. + + GV* gv_fetchmethod (HV* stash, char* name) + GV* gv_fetchmethod_autoload (HV* stash, char* name, I32 autoload) + +=item G_VOID - GV* gv_fetchmethod _((HV* stash, char* name)); +Used to indicate void context. See C and L. =item gv_stashpv @@ -1415,13 +1806,13 @@ Returns a pointer to the stash for a specified package. If C is set then the package will be created if it does not already exist. If C is not set and the package does not exist then NULL is returned. - HV* gv_stashpv _((char* name, I32 create)); + HV* gv_stashpv (char* name, I32 create) =item gv_stashsv Returns a pointer to the stash for a specified package. See C. - HV* gv_stashsv _((SV* sv, I32 create)); + HV* gv_stashsv (SV* sv, I32 create) =item GvSV @@ -1435,9 +1826,9 @@ C pointer is to be expected. (For information only--not to be used). =item HeHASH -Returns the computed hash (type C) stored in the hash entry. +Returns the computed hash stored in the hash entry. - HeHASH(HE* he) + U32 HeHASH(HE* he) =item HeKEY @@ -1446,7 +1837,7 @@ The pointer may be either C or C, depending on the value of C. Can be assigned to. The C or C macros are usually preferable for finding the value of a key. - HeKEY(HE* he) + char* HeKEY(HE* he) =item HeKLEN @@ -1455,7 +1846,7 @@ holds an C key. Otherwise, holds the actual length of the key. Can be assigned to. The C macro is usually preferable for finding key lengths. - HeKLEN(HE* he) + int HeKLEN(HE* he) =item HePV @@ -1463,13 +1854,13 @@ Returns the key slot of the hash entry as a C value, doing any necessary dereferencing of possibly C keys. The length of the string is placed in C (this is a macro, so do I use C<&len>). If you do not care about what the length of the key is, -you may use the global variable C. Remember though, that hash +you may use the global variable C. Remember though, that hash keys in perl are free to contain embedded nulls, so using C or similar is not a good way to find the length of hash keys. This is very similar to the C macro described elsewhere in this document. - HePV(HE* he, STRLEN len) + char* HePV(HE* he, STRLEN len) =item HeSVKEY @@ -1502,48 +1893,39 @@ Returns the value slot (type C) stored in the hash entry. Clears a hash, making it empty. - void hv_clear _((HV* tb)); - -=item hv_delayfree_ent - -Releases a hash entry, such as while iterating though the hash, but -delays actual freeing of key and value until the end of the current -statement (or thereabouts) with C. See C -and C. - - void hv_delayfree_ent _((HV* hv, HE* entry)); + void hv_clear (HV* tb) =item hv_delete Deletes a key/value pair in the hash. The value SV is removed from the hash and returned to the caller. The C is the length of the key. The -C value will normally be zero; if set to G_DISCARD then null will be +C value will normally be zero; if set to G_DISCARD then NULL will be returned. - SV* hv_delete _((HV* tb, char* key, U32 klen, I32 flags)); + SV* hv_delete (HV* tb, char* key, U32 klen, I32 flags) =item 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 C value will normally be zero; if set -to G_DISCARD then null will be returned. C can be a valid pre-computed +to G_DISCARD then NULL will be returned. C 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)); + SV* hv_delete_ent (HV* tb, SV* key, I32 flags, U32 hash) =item hv_exists Returns a boolean indicating whether the specified hash key exists. The C is the length of the key. - bool hv_exists _((HV* tb, char* key, U32 klen)); + bool hv_exists (HV* tb, char* key, U32 klen) =item hv_exists_ent Returns a boolean indicating whether the specified hash key exists. C -can be a valid pre-computed hash value, or 0 to ask for it to be computed. +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)); + bool hv_exists_ent (HV* tb, SV* key, U32 hash) =item hv_fetch @@ -1552,39 +1934,46 @@ C is the length of the key. If C is set then the fetch will be part of a store. Check that the return value is non-null before dereferencing it to a C. - SV** hv_fetch _((HV* tb, char* key, U32 klen, I32 lval)); +See L for more +information on how to use this function on tied hashes. + + SV** hv_fetch (HV* tb, char* key, U32 klen, I32 lval) =item hv_fetch_ent Returns the hash entry which corresponds to the specified key in the hash. -C must be a valid pre-computed hash number for the given C, or +C must be a valid precomputed hash number for the given C, or 0 if you want the function to compute it. IF C 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 C 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. - HE* hv_fetch_ent _((HV* tb, SV* key, I32 lval, U32 hash)); - -=item hv_free_ent +See L for more +information on how to use this function on tied hashes. -Releases a hash entry, such as while iterating though the hash. See -C and C. - - void hv_free_ent _((HV* hv, HE* entry)); + HE* hv_fetch_ent (HV* tb, SV* key, I32 lval, U32 hash) =item hv_iterinit Prepares a starting point to traverse a hash table. - I32 hv_iterinit _((HV* tb)); + I32 hv_iterinit (HV* tb) + +Returns the number of keys in the hash (i.e. the same as C). +The return value is currently only meaningful for hashes without tie +magic. + +NOTE: Before version 5.004_65, C 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 C. =item hv_iterkey Returns the key from the current position of the hash iterator. See C. - char* hv_iterkey _((HE* entry, I32* retlen)); + char* hv_iterkey (HE* entry, I32* retlen) =item hv_iterkeysv @@ -1592,104 +1981,116 @@ Returns the key as an C from the current position of the hash iterator. The return value will always be a mortal copy of the key. Also see C. - SV* hv_iterkeysv _((HE* entry)); + SV* hv_iterkeysv (HE* entry) =item hv_iternext Returns entries from a hash iterator. See C. - HE* hv_iternext _((HV* tb)); + HE* hv_iternext (HV* tb) =item hv_iternextsv Performs an C, C, and C in one operation. - SV * hv_iternextsv _((HV* hv, char** key, I32* retlen)); + SV* hv_iternextsv (HV* hv, char** key, I32* retlen) =item hv_iterval Returns the value from the current position of the hash iterator. See C. - SV* hv_iterval _((HV* tb, HE* entry)); + SV* hv_iterval (HV* tb, HE* entry) =item hv_magic Adds magic to a hash. See C. - void hv_magic _((HV* hv, GV* gv, int how)); + void hv_magic (HV* hv, GV* gv, int how) =item HvNAME Returns the package name of a stash. See C, C. - char *HvNAME (HV* stash) + char* HvNAME (HV* stash) =item hv_store Stores an SV in a hash. The hash key is specified as C and C is -the length of the key. The C parameter is the pre-computed hash +the length of the key. The C parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value will be -null if the operation failed, otherwise it can be dereferenced to get the -original C. +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 C. Note that the caller is +responsible for suitably incrementing the reference count of C +before the call, and decrementing it if the function returned NULL. - SV** hv_store _((HV* tb, char* key, U32 klen, SV* val, U32 hash)); +See L for more +information on how to use this function on tied hashes. + + SV** hv_store (HV* tb, char* key, U32 klen, SV* val, U32 hash) =item hv_store_ent Stores C in a hash. The hash key is specified as C. The C -parameter is the pre-computed hash value; if it is zero then Perl will +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 entry was stored in a tied hash. -Otherwise the contents of the return value can be accessed using the -C macros described here. +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 C macros +described here. Note that the caller is responsible for suitably +incrementing the reference count of C before the call, and decrementing +it if the function returned NULL. + +See L for more +information on how to use this function on tied hashes. - HE* hv_store_ent _((HV* tb, SV* key, SV* val, U32 hash)); + HE* hv_store_ent (HV* tb, SV* key, SV* val, U32 hash) =item hv_undef Undefines the hash. - void hv_undef _((HV* tb)); + void hv_undef (HV* tb) =item isALNUM Returns a boolean indicating whether the C C is an ascii alphanumeric character or digit. - int isALNUM (char c) + int isALNUM (char c) =item isALPHA Returns a boolean indicating whether the C C is an ascii alphabetic character. - int isALPHA (char c) + int isALPHA (char c) =item isDIGIT Returns a boolean indicating whether the C C is an ascii digit. - int isDIGIT (char c) + int isDIGIT (char c) =item isLOWER Returns a boolean indicating whether the C C is a lowercase character. - int isLOWER (char c) + int isLOWER (char c) =item isSPACE Returns a boolean indicating whether the C C is whitespace. - int isSPACE (char c) + int isSPACE (char c) =item isUPPER Returns a boolean indicating whether the C C is an uppercase character. - int isUPPER (char c) + int isUPPER (char c) =item items @@ -1707,6 +2108,13 @@ Closing bracket on a callback. See C and L. LEAVE; +=item looks_like_number + +Test if an the content of an SV looks like a number (or is a number). + + int looks_like_number(SV*) + + =item MARK Stack marker variable for the XSUB. See C. @@ -1715,59 +2123,59 @@ Stack marker variable for the XSUB. See C. Clear something magical that the SV represents. See C. - int mg_clear _((SV* sv)); + int mg_clear (SV* sv) =item mg_copy Copies the magic from one SV to another. See C. - int mg_copy _((SV *, SV *, char *, STRLEN)); + int mg_copy (SV *, SV *, char *, STRLEN) =item mg_find Finds the magic pointer for type matching the SV. See C. - MAGIC* mg_find _((SV* sv, int type)); + MAGIC* mg_find (SV* sv, int type) =item mg_free Free any magic storage used by the SV. See C. - int mg_free _((SV* sv)); + int mg_free (SV* sv) =item mg_get Do magic after a value is retrieved from the SV. See C. - int mg_get _((SV* sv)); + int mg_get (SV* sv) =item mg_len Report on the SV's length. See C. - U32 mg_len _((SV* sv)); + U32 mg_len (SV* sv) =item mg_magical Turns on the magical status of an SV. See C. - void mg_magical _((SV* sv)); + void mg_magical (SV* sv) =item mg_set Do magic after a value is assigned to the SV. See C. - int mg_set _((SV* sv)); + int mg_set (SV* sv) =item Move The XSUB-writer's interface to the C C function. The C is the source, C is the destination, C is the number of items, and C is -the type. +the type. Can do overlapping moves. See also C. - (void) Move( s, d, n, t ); + void Move( s, d, n, t ) -=item na +=item PL_na A variable which may be used with C to tell Perl to calculate the string length. @@ -1776,39 +2184,39 @@ string length. The XSUB-writer's interface to the C C function. - void * New( x, void *ptr, int size, type ) + void* New( x, void *ptr, int size, type ) -=item Newc +=item newAV -The XSUB-writer's interface to the C C function, with cast. +Creates a new AV. The reference count is set to 1. - void * Newc( x, void *ptr, int size, type, cast ) + AV* newAV (void) -=item Newz +=item Newc -The XSUB-writer's interface to the C C function. The allocated -memory is zeroed with C. +The XSUB-writer's interface to the C C function, with cast. - void * Newz( x, void *ptr, int size, type ) + void* Newc( x, void *ptr, int size, type, cast ) -=item newAV +=item newCONSTSUB -Creates a new AV. The reference count is set to 1. +Creates a constant sub equivalent to Perl C +which is eligible for inlining at compile-time. - AV* newAV _((void)); + void newCONSTSUB(HV* stash, char* name, SV* sv) =item newHV Creates a new HV. The reference count is set to 1. - HV* newHV _((void)); + HV* newHV (void) =item newRV_inc Creates an RV wrapper for an SV. The reference count for the original SV is incremented. - SV* newRV_inc _((SV* ref)); + SV* newRV_inc (SV* ref) For historical reasons, "newRV" is a synonym for "newRV_inc". @@ -1817,36 +2225,54 @@ For historical reasons, "newRV" is a synonym for "newRV_inc". Creates an RV wrapper for an SV. The reference count for the original SV is B incremented. - SV* newRV_noinc _((SV* ref)); + SV* newRV_noinc (SV* ref) -=item newSV +=item NEWSV -Creates a new SV. The C parameter indicates the number of bytes of -preallocated string space the SV should have. The reference count for the -new SV is set to 1. +Creates a new SV. A non-zero C 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. C is an integer id between 0 and 1299 (used to identify +leaks). - SV* newSV _((STRLEN len)); + SV* NEWSV (int id, STRLEN len) =item 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)); + SV* newSViv (IV i) =item newSVnv Creates a new SV and copies a double into it. The reference count for the SV is set to 1. - SV* newSVnv _((NV i)); + SV* newSVnv (NV i) =item newSVpv Creates a new SV and copies a string into it. The reference count for the SV is set to 1. If C is zero then Perl will compute the length. - SV* newSVpv _((char* s, STRLEN len)); + SV* newSVpv (char* s, STRLEN len) + +=item newSVpvf + +Creates a new SV an initialize it with the string formatted like +C. + + SV* newSVpvf(const char* pat, ...); + +=item newSVpvn + +Creates a new SV and copies a string into it. The reference count for the +SV is set to 1. If C is zero then Perl will create a zero length +string. + + SV* newSVpvn (char* s, STRLEN len) =item newSVrv @@ -1855,13 +2281,13 @@ it will be upgraded to one. If C 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, char* classname)); + SV* newSVrv (SV* rv, char* classname) =item newSVsv Creates a new SV which is an exact duplicate of the original SV. - SV* newSVsv _((SV* old)); + SV* newSVsv (SV* old) =item newXS @@ -1872,6 +2298,13 @@ Used by C to hook up XSUBs as Perl subs. Used by C to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs. +=item Newz + +The XSUB-writer's interface to the C C function. The allocated +memory is zeroed with C. + + void* Newz( x, void *ptr, int size, type ) + =item Nullav Null AV pointer. @@ -1904,27 +2337,27 @@ Allocates a new Perl interpreter. See L. Performs a callback to the specified Perl sub. See L. - I32 perl_call_argv _((char* subname, I32 flags, char** argv)); + I32 perl_call_argv (char* subname, I32 flags, char** argv) =item perl_call_method Performs a callback to the specified Perl method. The blessed object must be on the stack. See L. - I32 perl_call_method _((char* methname, I32 flags)); + I32 perl_call_method (char* methname, I32 flags) =item perl_call_pv Performs a callback to the specified Perl sub. See L. - I32 perl_call_pv _((char* subname, I32 flags)); + I32 perl_call_pv (char* subname, I32 flags) =item perl_call_sv Performs a callback to the Perl sub whose name is in the SV. See L. - I32 perl_call_sv _((SV* sv, I32 flags)); + I32 perl_call_sv (SV* sv, I32 flags) =item perl_construct @@ -1938,7 +2371,13 @@ Shuts down a Perl interpreter. See L. Tells Perl to C the string in the SV. - I32 perl_eval_sv _((SV* sv, I32 flags)); + I32 perl_eval_sv (SV* sv, I32 flags) + +=item perl_eval_pv + +Tells Perl to C the given string and return an SV* result. + + SV* perl_eval_pv (char* p, I32 croak_on_error) =item perl_free @@ -1948,33 +2387,33 @@ Releases a Perl interpreter. See L. Returns the AV of the specified Perl array. If C is set and the Perl variable does not exist then it will be created. If C is not -set and the variable does not exist then null is returned. +set and the variable does not exist then NULL is returned. - AV* perl_get_av _((char* name, I32 create)); + AV* perl_get_av (char* name, I32 create) =item perl_get_cv Returns the CV of the specified Perl sub. If C is set and the Perl variable does not exist then it will be created. If C is not -set and the variable does not exist then null is returned. +set and the variable does not exist then NULL is returned. - CV* perl_get_cv _((char* name, I32 create)); + CV* perl_get_cv (char* name, I32 create) =item perl_get_hv Returns the HV of the specified Perl hash. If C is set and the Perl variable does not exist then it will be created. If C is not -set and the variable does not exist then null is returned. +set and the variable does not exist then NULL is returned. - HV* perl_get_hv _((char* name, I32 create)); + HV* perl_get_hv (char* name, I32 create) =item perl_get_sv Returns the SV of the specified Perl scalar. If C is set and the Perl variable does not exist then it will be created. If C is not -set and the variable does not exist then null is returned. +set and the variable does not exist then NULL is returned. - SV* perl_get_sv _((char* name, I32 create)); + SV* perl_get_sv (char* name, I32 create) =item perl_parse @@ -1984,7 +2423,7 @@ Tells a Perl interpreter to parse a Perl script. See L. Tells Perl to C a module. - void perl_require_pv _((char* pv)); + void perl_require_pv (char* pv) =item perl_run @@ -1994,31 +2433,31 @@ Tells a Perl interpreter to run. See L. Pops an integer off the stack. - int POPi(); + int POPi() =item POPl Pops a long off the stack. - long POPl(); + long POPl() =item POPp Pops a string off the stack. - char * POPp(); + char* POPp() =item POPn Pops a double off the stack. - double POPn(); + double POPn() =item POPs Pops an SV off the stack. - SV* POPs(); + SV* POPs() =item PUSHMARK @@ -2029,30 +2468,39 @@ Opening bracket for arguments on a callback. See C and L. =item PUSHi Push an integer onto the stack. The stack must have room for this element. -See C. +Handles 'set' magic. See C. - PUSHi(int d) + void PUSHi(int d) =item PUSHn Push a double onto the stack. The stack must have room for this element. -See C. +Handles 'set' magic. See C. - PUSHn(double d) + void PUSHn(double d) =item PUSHp Push a string onto the stack. The stack must have room for this element. -The C indicates the length of the string. See C. +The C indicates the length of the string. Handles 'set' magic. See +C. - PUSHp(char *c, int len ) + void PUSHp(char *c, int len ) =item PUSHs -Push an SV onto the stack. The stack must have room for this element. See -C. +Push an SV onto the stack. The stack must have room for this element. Does +not handle 'set' magic. See C. + + void PUSHs(sv) + +=item PUSHu + +Push an unsigned integer onto the stack. The stack must have room for +this element. See C. + + void PUSHu(unsigned int d) - PUSHs(sv) =item PUTBACK @@ -2065,13 +2513,13 @@ See C and L for other uses. The XSUB-writer's interface to the C C function. - void * Renew( void *ptr, int size, type ) + void* Renew( void *ptr, int size, type ) =item Renewc The XSUB-writer's interface to the C C function, with cast. - void * Renewc( void *ptr, int size, type, cast ) + void* Renewc( void *ptr, int size, type, cast ) =item RETVAL @@ -2095,14 +2543,14 @@ The XSUB-writer's interface to the C C function. Copy a string to a safe spot. This does not use an SV. - char* savepv _((char* sv)); + char* savepv (char* sv) =item savepvn Copy a string to a safe spot. The C indicates number of bytes to copy. This does not use an SV. - char* savepvn _((char* sv, I32 len)); + char* savepvn (char* sv, I32 len) =item SAVETMPS @@ -2118,7 +2566,7 @@ C. =item SPAGAIN -Re-fetch the stack pointer. Used after a callback. See L. +Refetch the stack pointer. Used after a callback. See L. SPAGAIN; @@ -2126,68 +2574,68 @@ Re-fetch the stack pointer. Used after a callback. See L. Used to access elements on the XSUB's stack. - SV* ST(int x) + SV* ST(int x) =item strEQ Test two strings to see if they are equal. Returns true or false. - int strEQ( char *s1, char *s2 ) + int strEQ( char *s1, char *s2 ) =item strGE Test two strings to see if the first, C, is greater than or equal to the second, C. Returns true or false. - int strGE( char *s1, char *s2 ) + int strGE( char *s1, char *s2 ) =item strGT Test two strings to see if the first, C, is greater than the second, C. Returns true or false. - int strGT( char *s1, char *s2 ) + int strGT( char *s1, char *s2 ) =item strLE Test two strings to see if the first, C, is less than or equal to the second, C. Returns true or false. - int strLE( char *s1, char *s2 ) + int strLE( char *s1, char *s2 ) =item strLT Test two strings to see if the first, C, is less than the second, C. Returns true or false. - int strLT( char *s1, char *s2 ) + int strLT( char *s1, char *s2 ) =item strNE Test two strings to see if they are different. Returns true or false. - int strNE( char *s1, char *s2 ) + int strNE( char *s1, char *s2 ) =item strnEQ Test two strings to see if they are equal. The C parameter indicates the number of bytes to compare. Returns true or false. - int strnEQ( char *s1, char *s2 ) + int strnEQ( char *s1, char *s2 ) =item strnNE Test two strings to see if they are different. The C parameter indicates the number of bytes to compare. Returns true or false. - int strnNE( char *s1, char *s2, int len ) + int strnNE( char *s1, char *s2, int len ) =item sv_2mortal Marks an SV as mortal. The SV will be destroyed when the current context ends. - SV* sv_2mortal _((SV* sv)); + SV* sv_2mortal (SV* sv) =item sv_bless @@ -2195,35 +2643,71 @@ Blesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (see C). The reference count of the SV is unaffected. - SV* sv_bless _((SV* sv, HV* stash)); + SV* sv_bless (SV* sv, HV* stash) =item sv_catpv Concatenates the string onto the end of the string which is in the SV. +Handles 'get' magic, but not 'set' magic. See C. + + void sv_catpv (SV* sv, char* ptr) + +=item sv_catpv_mg + +Like C, but also handles 'set' magic. - void sv_catpv _((SV* sv, char* ptr)); + void sv_catpvn (SV* sv, char* ptr) =item sv_catpvn Concatenates the string onto the end of the string which is in the SV. The -C indicates number of bytes to copy. +C indicates number of bytes to copy. Handles 'get' magic, but not +'set' magic. See C. + + void sv_catpvn (SV* sv, char* ptr, STRLEN len) + +=item sv_catpvn_mg + +Like C, but also handles 'set' magic. + + void sv_catpvn_mg (SV* sv, char* ptr, STRLEN len) - void sv_catpvn _((SV* sv, char* ptr, STRLEN len)); +=item sv_catpvf + +Processes its arguments like C and appends the formatted output +to an SV. Handles 'get' magic, but not 'set' magic. C must +typically be called after calling this function to handle 'set' magic. + + void sv_catpvf (SV* sv, const char* pat, ...) + +=item sv_catpvf_mg + +Like C, but also handles 'set' magic. + + void sv_catpvf_mg (SV* sv, const char* pat, ...) =item sv_catsv Concatenates the string from SV C onto the end of the string in SV -C. +C. Handles 'get' magic, but not 'set' magic. See C. - void sv_catsv _((SV* dsv, SV* ssv)); + void sv_catsv (SV* dsv, SV* ssv) -=item sv_cmp +=item sv_catsv_mg -Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the -string in C is less than, equal to, or greater than the string in -C. +Like C, but also handles 'set' magic. + + void sv_catsv_mg (SV* dsv, SV* ssv) + +=item sv_chop + +Efficient removal of characters from the beginning of the string +buffer. SvPOK(sv) must be true and the C must be a pointer to +somewhere inside the string buffer. The C becomes the first +character of the adjusted string. + + void sv_chop(SV* sv, char *ptr) - I32 sv_cmp _((SV* sv1, SV* sv2)); =item sv_cmp @@ -2231,52 +2715,70 @@ Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in C is less than, equal to, or greater than the string in C. - I32 sv_cmp _((SV* sv1, SV* sv2)); + I32 sv_cmp (SV* sv1, SV* sv2) =item SvCUR Returns the length of the string which is in the SV. See C. - int SvCUR (SV* sv) + int SvCUR (SV* sv) =item SvCUR_set Set the length of the string which is in the SV. See C. - SvCUR_set (SV* sv, int val ) + void SvCUR_set (SV* sv, int val ) =item sv_dec Auto-decrement of the value in the SV. - void sv_dec _((SV* sv)); + void sv_dec (SV* sv) -=item sv_dec +=item sv_derived_from -Auto-decrement of the value in the SV. +Returns a boolean indicating whether the SV is a subclass of the +specified class. + + int sv_derived_from(SV* sv, char* class) + +=item sv_derived_from + +Returns a boolean indicating whether the SV is derived from the specified +class. This is the function that implements C. It works +for class names as well as for objects. - void sv_dec _((SV* sv)); + bool sv_derived_from _((SV* sv, char* name)); =item SvEND Returns a pointer to the last character in the string which is in the SV. See C. Access the character as - *SvEND(sv) + char* SvEND(sv) =item sv_eq Returns a boolean indicating whether the strings in the two SVs are identical. - I32 sv_eq _((SV* sv1, SV* sv2)); + I32 sv_eq (SV* sv1, SV* sv2) + +=item SvGETMAGIC + +Invokes C on an SV if it has 'get' magic. This macro evaluates +its argument more than once. + + void SvGETMAGIC( SV *sv ) =item SvGROW -Expands the character buffer in the SV. Calls C to perform the -expansion if necessary. Returns a pointer to the character buffer. +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 C to perform the expansion if +necessary. Returns a pointer to the character buffer. - char * SvGROW( SV* sv, int len ) + char* SvGROW( SV* sv, int len ) =item sv_grow @@ -2288,58 +2790,54 @@ Use C. Auto-increment of the value in the SV. - void sv_inc _((SV* sv)); + void sv_inc (SV* sv) + +=item sv_insert + +Inserts a string at the specified offset/length within the SV. +Similar to the Perl substr() function. + + void sv_insert(SV *sv, STRLEN offset, STRLEN len, + char *str, STRLEN strlen) =item SvIOK Returns a boolean indicating whether the SV contains an integer. - int SvIOK (SV* SV) + int SvIOK (SV* SV) =item SvIOK_off Unsets the IV status of an SV. - SvIOK_off (SV* sv) + void SvIOK_off (SV* sv) =item SvIOK_on Tells an SV that it is an integer. - SvIOK_on (SV* sv) + void SvIOK_on (SV* sv) =item SvIOK_only Tells an SV that it is an integer and disables all other OK bits. - SvIOK_on (SV* sv) - -=item SvIOK_only - -Tells an SV that it is an integer and disables all other OK bits. - - SvIOK_on (SV* sv) + void SvIOK_only (SV* sv) =item SvIOKp Returns a boolean indicating whether the SV contains an integer. Checks the B setting. Use C. - int SvIOKp (SV* SV) + int SvIOKp (SV* SV) =item sv_isa Returns a boolean indicating whether the SV is blessed into the specified -class. This does not know how to check for subtype, so it doesn't work in +class. This does not check for subtypes; use C to verify an inheritance relationship. - int sv_isa _((SV* sv, char* name)); - -=item SvIV - -Returns the integer which is in the SV. - - int SvIV (SV* sv) + int sv_isa (SV* sv, char* name) =item sv_isobject @@ -2347,247 +2845,312 @@ 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)); + int sv_isobject (SV* sv) + +=item SvIV + +Returns the integer which is in the SV. + + int SvIV (SV* sv) =item SvIVX Returns the integer which is stored in the SV. - int SvIVX (SV* sv); + int SvIVX (SV* sv) =item SvLEN Returns the size of the string buffer in the SV. See C. - int SvLEN (SV* sv) - -=item sv_len - -Returns the length of the string in the SV. Use C. - - STRLEN sv_len _((SV* sv)); + int SvLEN (SV* sv) =item sv_len Returns the length of the string in the SV. Use C. - STRLEN sv_len _((SV* sv)); + STRLEN sv_len (SV* sv) =item sv_magic Adds magic to an SV. - void sv_magic _((SV* sv, SV* obj, int how, char* name, I32 namlen)); + void sv_magic (SV* sv, SV* obj, int how, char* name, I32 namlen) =item sv_mortalcopy Creates a new SV which is a copy of the original SV. The new SV is marked as mortal. - SV* sv_mortalcopy _((SV* oldsv)); - -=item SvOK - -Returns a boolean indicating whether the value is an SV. - - int SvOK (SV* sv) + SV* sv_mortalcopy (SV* oldsv) =item sv_newmortal Creates a new SV which is mortal. The reference count of the SV is set to 1. - SV* sv_newmortal _((void)); - -=item sv_no - -This is the C SV. See C. Always refer to this as C<&sv_no>. + SV* sv_newmortal (void) =item SvNIOK Returns a boolean indicating whether the SV contains a number, integer or double. - int SvNIOK (SV* SV) + int SvNIOK (SV* SV) =item SvNIOK_off Unsets the NV/IV status of an SV. - SvNIOK_off (SV* sv) + void SvNIOK_off (SV* sv) =item SvNIOKp Returns a boolean indicating whether the SV contains a number, integer or double. Checks the B setting. Use C. - int SvNIOKp (SV* SV) + int SvNIOKp (SV* SV) + +=item PL_sv_no + +This is the C SV. See C. Always refer to this as C<&PL_sv_no>. =item SvNOK Returns a boolean indicating whether the SV contains a double. - int SvNOK (SV* SV) + int SvNOK (SV* SV) =item SvNOK_off Unsets the NV status of an SV. - SvNOK_off (SV* sv) + void SvNOK_off (SV* sv) =item SvNOK_on Tells an SV that it is a double. - SvNOK_on (SV* sv) + void SvNOK_on (SV* sv) =item SvNOK_only Tells an SV that it is a double and disables all other OK bits. - SvNOK_on (SV* sv) - -=item SvNOK_only - -Tells an SV that it is a double and disables all other OK bits. - - SvNOK_on (SV* sv) + void SvNOK_only (SV* sv) =item SvNOKp Returns a boolean indicating whether the SV contains a double. Checks the B setting. Use C. - int SvNOKp (SV* SV) + int SvNOKp (SV* SV) =item SvNV Returns the double which is stored in the SV. - double SvNV (SV* sv); + double SvNV (SV* sv) =item SvNVX Returns the double which is stored in the SV. - double SvNVX (SV* sv); + double SvNVX (SV* sv) + +=item SvOK + +Returns a boolean indicating whether the value is an SV. + + int SvOK (SV* sv) + +=item 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). + + int SvOOK(SV* sv) =item SvPOK Returns a boolean indicating whether the SV contains a character string. - int SvPOK (SV* SV) + int SvPOK (SV* SV) =item SvPOK_off Unsets the PV status of an SV. - SvPOK_off (SV* sv) + void SvPOK_off (SV* sv) =item SvPOK_on Tells an SV that it is a string. - SvPOK_on (SV* sv) + void SvPOK_on (SV* sv) =item SvPOK_only Tells an SV that it is a string and disables all other OK bits. - SvPOK_on (SV* sv) - -=item SvPOK_only - -Tells an SV that it is a string and disables all other OK bits. - - SvPOK_on (SV* sv) + void SvPOK_only (SV* sv) =item SvPOKp Returns a boolean indicating whether the SV contains a character string. Checks the B setting. Use C. - int SvPOKp (SV* SV) + int SvPOKp (SV* SV) =item 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. If C is C then Perl will -handle the length on its own. +if the SV does not contain a string. If C is C then Perl will +handle the length on its own. Handles 'get' magic. + + char* SvPV (SV* sv, int len ) + +=item SvPV_force + +Like but will force the SV into becoming a string (SvPOK). You +want force if you are going to update the SvPVX directly. + + char* SvPV_force(SV* sv, int len) - char * SvPV (SV* sv, int len ) =item SvPVX Returns a pointer to the string in the SV. The SV must contain a string. - char * SvPVX (SV* sv) + char* SvPVX (SV* sv) =item SvREFCNT Returns the value of the object's reference count. - int SvREFCNT (SV* sv); + int SvREFCNT (SV* sv) =item SvREFCNT_dec Decrements the reference count of the given SV. - void SvREFCNT_dec (SV* sv) + void SvREFCNT_dec (SV* sv) =item SvREFCNT_inc Increments the reference count of the given SV. - void SvREFCNT_inc (SV* sv) + void SvREFCNT_inc (SV* sv) =item SvROK Tests if the SV is an RV. - int SvROK (SV* sv) + int SvROK (SV* sv) =item SvROK_off Unsets the RV status of an SV. - SvROK_off (SV* sv) + void SvROK_off (SV* sv) =item SvROK_on Tells an SV that it is an RV. - SvROK_on (SV* sv) + void SvROK_on (SV* sv) =item SvRV Dereferences an RV to return the SV. - SV* SvRV (SV* sv); + SV* SvRV (SV* sv) + +=item SvSETMAGIC + +Invokes C on an SV if it has 'set' magic. This macro evaluates +its argument more than once. + + void SvSETMAGIC( SV *sv ) =item sv_setiv -Copies an integer into the given SV. +Copies an integer into the given SV. Does not handle 'set' magic. +See C. - void sv_setiv _((SV* sv, IV num)); + void sv_setiv (SV* sv, IV num) + +=item sv_setiv_mg + +Like C, but also handles 'set' magic. + + void sv_setiv_mg (SV* sv, IV num) =item sv_setnv -Copies a double into the given SV. +Copies a double into the given SV. Does not handle 'set' magic. +See C. + + void sv_setnv (SV* sv, double num) - void sv_setnv _((SV* sv, double num)); +=item sv_setnv_mg + +Like C, but also handles 'set' magic. + + void sv_setnv_mg (SV* sv, double num) =item sv_setpv Copies a string into an SV. The string must be null-terminated. +Does not handle 'set' magic. See C. + + void sv_setpv (SV* sv, char* ptr) + +=item sv_setpv_mg + +Like C, but also handles 'set' magic. + + void sv_setpv_mg (SV* sv, char* ptr) + +=item sv_setpviv + +Copies an integer into the given SV, also updating its string value. +Does not handle 'set' magic. See C. + + void sv_setpviv (SV* sv, IV num) - void sv_setpv _((SV* sv, char* ptr)); +=item sv_setpviv_mg + +Like C, but also handles 'set' magic. + + void sv_setpviv_mg (SV* sv, IV num) =item sv_setpvn Copies a string into an SV. The C parameter indicates the number of -bytes to be copied. +bytes to be copied. Does not handle 'set' magic. See C. + + void sv_setpvn (SV* sv, char* ptr, STRLEN len) + +=item sv_setpvn_mg + +Like C, but also handles 'set' magic. + + void sv_setpvn_mg (SV* sv, char* ptr, STRLEN len) + +=item sv_setpvf + +Processes its arguments like C and sets an SV to the formatted +output. Does not handle 'set' magic. See C. + + void sv_setpvf (SV* sv, const char* pat, ...) + +=item sv_setpvf_mg - void sv_setpvn _((SV* sv, char* ptr, STRLEN len)); +Like C, but also handles 'set' magic. + + void sv_setpvf_mg (SV* sv, const char* pat, ...) =item sv_setref_iv @@ -2597,7 +3160,7 @@ the new SV. The C argument indicates the package for the blessing. Set C to C to avoid the blessing. The new SV will be returned and will have a reference count of 1. - SV* sv_setref_iv _((SV *rv, char *classname, IV iv)); + SV* sv_setref_iv (SV *rv, char *classname, IV iv) =item sv_setref_nv @@ -2607,18 +3170,18 @@ the new SV. The C argument indicates the package for the blessing. Set C to C to avoid the blessing. The new SV will be returned and will have a reference count of 1. - SV* sv_setref_nv _((SV *rv, char *classname, double nv)); + SV* sv_setref_nv (SV *rv, char *classname, double nv) =item sv_setref_pv Copies a pointer into a new SV, optionally blessing the SV. The C argument will be upgraded to an RV. That RV will be modified to point to -the new SV. If the C argument is NULL then C will be placed +the new SV. If the C argument is NULL then C will be placed into the SV. The C argument indicates the package for the blessing. Set C to C to avoid the blessing. The new SV will be returned and will have a reference count of 1. - SV* sv_setref_pv _((SV *rv, char *classname, void* pv)); + SV* sv_setref_pv (SV *rv, char *classname, void* pv) Do not use with integral Perl types such as HV, AV, SV, CV, because those objects will become corrupted by the pointer copy process. @@ -2634,22 +3197,85 @@ argument indicates the package for the blessing. Set C to C to avoid the blessing. The new SV will be returned and will have a reference count of 1. - SV* sv_setref_pvn _((SV *rv, char *classname, char* pv, I32 n)); + SV* sv_setref_pvn (SV *rv, char *classname, char* pv, I32 n) Note that C copies the pointer while this copies the string. +=item SvSetSV + +Calls C if dsv is not the same as ssv. May evaluate arguments +more than once. + + void SvSetSV (SV* dsv, SV* ssv) + +=item SvSetSV_nosteal + +Calls a non-destructive version of C if dsv is not the same as ssv. +May evaluate arguments more than once. + + void SvSetSV_nosteal (SV* dsv, SV* ssv) + =item sv_setsv Copies the contents of the source SV C into the destination SV C. -The source SV may be destroyed if it is mortal. +The source SV may be destroyed if it is mortal. Does not handle 'set' magic. +See the macro forms C, C and C. + + void sv_setsv (SV* dsv, SV* ssv) + +=item sv_setsv_mg - void sv_setsv _((SV* dsv, SV* ssv)); +Like C, but also handles 'set' magic. + + void sv_setsv_mg (SV* dsv, SV* ssv) + +=item sv_setuv + +Copies an unsigned integer into the given SV. Does not handle 'set' magic. +See C. + + void sv_setuv (SV* sv, UV num) + +=item sv_setuv_mg + +Like C, but also handles 'set' magic. + + void sv_setuv_mg (SV* sv, UV num) =item SvSTASH Returns the stash of the SV. - HV * SvSTASH (SV* sv) + HV* SvSTASH (SV* sv) + +=item SvTAINT + +Taints an SV if tainting is enabled + + void SvTAINT (SV* sv) + +=item SvTAINTED + +Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not. + + int SvTAINTED (SV* sv) + +=item SvTAINTED_off + +Untaints an SV. Be I 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) + +=item SvTAINTED_on + +Marks an SV as tainted. + + void SvTAINTED_on (SV* sv) =item SVt_IV @@ -2682,9 +3308,9 @@ Double type flag for scalars. See C. =item SvTRUE Returns a boolean indicating whether Perl would evaluate the SV as true or -false, defined or undefined. +false, defined or undefined. Does not handle 'get' magic. - int SvTRUE (SV* sv) + int SvTRUE (SV* sv) =item SvTYPE @@ -2697,28 +3323,28 @@ Returns the type of the SV. See C. An enum of flags for Perl types. These are found in the file B in the C enum. Test these flags with the C macro. -=item SvUPGRADE +=item PL_sv_undef -Used to upgrade an SV to a more complex form. Uses C to perform -the upgrade if necessary. See C. +This is the C SV. Always refer to this as C<&PL_sv_undef>. - bool SvUPGRADE _((SV* sv, svtype mt)); +=item sv_unref -=item sv_upgrade +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 C. See C. -Upgrade an SV to a more complex form. Use C. See C. + void sv_unref (SV* sv) -=item sv_undef +=item SvUPGRADE -This is the C SV. Always refer to this as C<&sv_undef>. +Used to upgrade an SV to a more complex form. Uses C to perform +the upgrade if necessary. See C. -=item sv_unref + bool SvUPGRADE (SV* sv, svtype mt) -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 C. See C. +=item sv_upgrade - void sv_unref _((SV* sv)); +Upgrade an SV to a more complex form. Use C. See C. =item sv_usepvn @@ -2727,13 +3353,51 @@ stored inside the SV but sv_usepvn allows the SV to use an outside string. The C should point to memory that was allocated by C. The string length, C, must be supplied. This function will realloc the memory pointed to by C, so that pointer should not be freed or used by -the programmer after giving it to sv_usepvn. +the programmer after giving it to sv_usepvn. Does not handle 'set' magic. +See C. + + void sv_usepvn (SV* sv, char* ptr, STRLEN len) - void sv_usepvn _((SV* sv, char* ptr, STRLEN len)); +=item sv_usepvn_mg -=item sv_yes +Like C, but also handles 'set' magic. -This is the C SV. See C. Always refer to this as C<&sv_yes>. + void sv_usepvn_mg (SV* sv, char* ptr, STRLEN len) + +=item sv_vcatpvfn(sv, pat, patlen, args, svargs, svmax, used_locale) + +Processes its arguments like C and appends the formatted output +to an SV. Uses an array of SVs if the C style variable argument list is +missing (NULL). Indicates if locale information has been used for formatting. + + void sv_catpvfn _((SV* sv, const char* pat, STRLEN patlen, + va_list *args, SV **svargs, I32 svmax, + bool *used_locale)); + +=item sv_vsetpvfn(sv, pat, patlen, args, svargs, svmax, used_locale) + +Works like C but copies the text into the SV instead of +appending it. + + void sv_setpvfn _((SV* sv, const char* pat, STRLEN patlen, + va_list *args, SV **svargs, I32 svmax, + bool *used_locale)); + +=item SvUV + +Returns the unsigned integer which is in the SV. + + UV SvUV(SV* sv) + +=item SvUVX + +Returns the unsigned integer which is stored in the SV. + + UV SvUVX(SV* sv) + +=item PL_sv_yes + +This is the C SV. See C. Always refer to this as C<&PL_sv_yes>. =item THIS @@ -2745,13 +3409,13 @@ L. Converts the specified character to lowercase. - int toLOWER (char c) + int toLOWER (char c) =item toUPPER Converts the specified character to uppercase. - int toUPPER (char c) + int toUPPER (char c) =item warn @@ -2760,31 +3424,37 @@ function the same way you use the C C function. See C. =item XPUSHi -Push an integer onto the stack, extending the stack if necessary. See -C. +Push an integer onto the stack, extending the stack if necessary. Handles +'set' magic. See C. XPUSHi(int d) =item XPUSHn -Push a double onto the stack, extending the stack if necessary. See -C. +Push a double onto the stack, extending the stack if necessary. Handles 'set' +magic. See C. XPUSHn(double d) =item XPUSHp Push a string onto the stack, extending the stack if necessary. The C -indicates the length of the string. See C. +indicates the length of the string. Handles 'set' magic. See C. XPUSHp(char *c, int len) =item XPUSHs -Push an SV onto the stack, extending the stack if necessary. See C. +Push an SV onto the stack, extending the stack if necessary. Does not +handle 'set' magic. See C. XPUSHs(sv) +=item XPUSHu + +Push an unsigned integer onto the stack, extending the stack if +necessary. See C. + =item XS Macro to declare an XSUB and its C parameter list. This is handled by @@ -2795,7 +3465,7 @@ C. Return from XSUB, indicating number of items on the stack. This is usually handled by C. - XSRETURN(int x); + XSRETURN(int x) =item XSRETURN_EMPTY @@ -2807,11 +3477,11 @@ Return an empty list from an XSUB immediately. Return an integer from an XSUB immediately. Uses C. - XSRETURN_IV(IV v); + XSRETURN_IV(IV v) =item XSRETURN_NO -Return C<&sv_no> from an XSUB immediately. Uses C. +Return C<&PL_sv_no> from an XSUB immediately. Uses C. XSRETURN_NO; @@ -2819,23 +3489,23 @@ Return C<&sv_no> from an XSUB immediately. Uses C. Return an double from an XSUB immediately. Uses C. - XSRETURN_NV(NV v); + XSRETURN_NV(NV v) =item XSRETURN_PV Return a copy of a string from an XSUB immediately. Uses C. - XSRETURN_PV(char *v); + XSRETURN_PV(char *v) =item XSRETURN_UNDEF -Return C<&sv_undef> from an XSUB immediately. Uses C. +Return C<&PL_sv_undef> from an XSUB immediately. Uses C. XSRETURN_UNDEF; =item XSRETURN_YES -Return C<&sv_yes> from an XSUB immediately. Uses C. +Return C<&PL_sv_yes> from an XSUB immediately. Uses C. XSRETURN_YES; @@ -2844,39 +3514,39 @@ Return C<&sv_yes> from an XSUB immediately. Uses C. Place an integer into the specified position C on the stack. The value is stored in a new mortal SV. - XST_mIV( int i, IV v ); + XST_mIV( int i, IV v ) =item XST_mNV Place a double into the specified position C on the stack. The value is stored in a new mortal SV. - XST_mNV( int i, NV v ); + XST_mNV( int i, NV v ) =item XST_mNO -Place C<&sv_no> into the specified position C on the stack. +Place C<&PL_sv_no> into the specified position C on the stack. - XST_mNO( int i ); + XST_mNO( int i ) =item XST_mPV Place a copy of a string into the specified position C on the stack. The value is stored in a new mortal SV. - XST_mPV( int i, char *v ); + XST_mPV( int i, char *v ) =item XST_mUNDEF -Place C<&sv_undef> into the specified position C on the stack. +Place C<&PL_sv_undef> into the specified position C on the stack. - XST_mUNDEF( int i ); + XST_mUNDEF( int i ) =item XST_mYES -Place C<&sv_yes> into the specified position C on the stack. +Place C<&PL_sv_yes> into the specified position C on the stack. - XST_mYES( int i ); + XST_mYES( int i ) =item XS_VERSION @@ -2894,20 +3564,18 @@ C. See L. The XSUB-writer's interface to the C C function. The C is the destination, C is the number of items, and C is the type. - (void) Zero( d, n, t ); + void Zero( d, n, t ) =back -=head1 EDITOR +=head1 AUTHORS -Jeff Okamoto > +Until May 1997, this document was maintained by Jeff Okamoto +. 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, and Ulrich Pfeifer. - -API Listing by Dean Roehrich >. - -=head1 DATE +Bowers, Matthew Green, Tim Bunce, Spider Boardman, Ulrich Pfeifer, +Stephen McCamant, and Gurusamy Sarathy. -Version 31.3: 1997/3/14 +API Listing originally by Dean Roehrich .