ST(0) = newSVpv("Hello World",0);
sv_2mortal(ST(0));
XSRETURN(1);
-
+
SV *
beta()
CODE:
is not properly decremented. Thus, the above XSUB would leak memory
whenever it is being called. The same problem exists for C<HV *>.
-When you're returning an C<AV *> or a C<HV *>, you have make sure
+When you're returning an C<AV *> or a C<HV *>, you have to make sure
their reference count is decremented by making the AV or HV mortal:
AV *
is quietly ignored.
The following code demonstrates how to supply initialization code for
-function parameters. The initialization code is eval'd within double
+function parameters. The initialization code is eval'ed within double
quotes by the compiler before it is added to the output so anything
which should be interpreted literally [mainly C<$>, C<@>, or C<\\>]
must be protected with backslashes. The variables $var, $arg,
bool_t
rpcb_gettime(host,timep)
- char *host = (char *)SvPV($arg,PL_na);
+ char *host = (char *)SvPV_nolen($arg);
time_t &timep = 0;
OUTPUT:
timep
bool_t
rpcb_gettime(host,timep)
time_t &timep; /* \$v{timep}=@{[$v{timep}=$arg]} */
- char *host + SvOK($v{timep}) ? SvPV($arg,PL_na) : NULL;
+ char *host + SvOK($v{timep}) ? SvPV_nolen($arg) : NULL;
OUTPUT:
timep
time_t timep = NO_INIT
PREINIT:
char *host = "localhost";
- STRLEN n_a;
CODE:
if( items > 1 )
- host = (char *)SvPV(ST(1), n_a);
+ host = (char *)SvPV_nolen(ST(1));
RETVAL = rpcb_gettime( host, &timep );
OUTPUT:
timep
time_t timep;
bool_t x;
CODE:
- ST(0) = sv_newmortal();
if( rpcb_gettime( host, &timep ) ){
+ ST(0) = sv_newmortal();
sv_setnv( ST(0), (double)timep);
}
else{
VERSIONCHECK: DISABLE
+Note that if the version of the PM module is an NV (a floating point
+number), it will be stringified with a possible loss of precision
+(currently chopping to nine decimal places) so that it may not match
+the version of the XS module anymore. Quoting the $VERSION declaration
+to make it a string is recommended if long version numbers are used.
+
=head2 The PROTOTYPES: Keyword
The PROTOTYPES: keyword corresponds to B<xsubpp>'s C<-prototypes> and
PROTOTYPE: $;$
PREINIT:
char *host = "localhost";
- STRLEN n_a;
CODE:
if( items > 1 )
- host = (char *)SvPV(ST(1), n_a);
+ host = (char *)SvPV_nolen(ST(1));
RETVAL = rpcb_gettime( host, &timep );
OUTPUT:
timep
In this case, the function will overload both of the three way
comparison operators. For all overload operations using non-alpha
-characters, you must type the parameter without quoting, seperating
+characters, you must type the parameter without quoting, separating
multiple overloads with whitespace. Note that "" (the stringify
overload) should be entered as \"\" (i.e. escaped).
C<subtract_off>. Then one can use
#define XSINTERFACE_FUNC_BYOFFSET(ret,cv,f) \
- ((XSINTERFACE_CVT(ret,))fp[CvXSUBANY(cv).any_i32])
+ ((XSINTERFACE_CVT_ANON(ret))fp[CvXSUBANY(cv).any_i32])
#define XSINTERFACE_FUNC_BYOFFSET_set(cv,f) \
CvXSUBANY(cv).any_i32 = CAT2( f, _off )
CODE:
MY_CXT_CLONE;
-
B<REFERENCE>
=over 5
=item typedef my_cxt_t
-This struct typedef I<must> always be called C<my_cxt_t> -- the other
+This struct typedef I<must> always be called C<my_cxt_t>. The other
C<CXT*> macros assume the existence of the C<my_cxt_t> typedef name.
Declare a typedef named C<my_cxt_t> that is a structure that contains
The MY_CXT_INIT macro initialises storage for the C<my_cxt_t> struct.
-It I<must> be called exactly once -- typically in a BOOT: section. If you
+It I<must> be called exactly once, typically in a BOOT: section. If you
are maintaining multiple interpreters, it should be called once in each
interpreter instance, except for interpreters cloned from existing ones.
(But see C<MY_CXT_CLONE> below.)
=item MY_CXT_CLONE
By default, when a new interpreter is created as a copy of an existing one
-(eg via C<<threads->new()>>), both interpreters share the same physical
+(eg via C<< threads->create() >>), both interpreters share the same physical
my_cxt_t structure. Calling C<MY_CXT_CLONE> (typically via the package's
C<CLONE()> function), causes a byte-for-byte copy of the structure to be
taken, and any future dMY_CXT will cause the copy to be accessed instead.
+=item MY_CXT_INIT_INTERP(my_perl)
+
+=item dMY_CXT_INTERP(my_perl)
+
+These are versions of the macros which take an explicit interpreter as an
+argument.
+
=back
+Note that these macros will only work together within the I<same> source
+file; that is, a dMY_CTX in one source file will access a different structure
+than a dMY_CTX in another source file.
+
+=head2 Thread-aware system interfaces
+
+Starting from Perl 5.8, in C/C++ level Perl knows how to wrap
+system/library interfaces that have thread-aware versions
+(e.g. getpwent_r()) into frontend macros (e.g. getpwent()) that
+correctly handle the multithreaded interaction with the Perl
+interpreter. This will happen transparently, the only thing
+you need to do is to instantiate a Perl interpreter.
+
+This wrapping happens always when compiling Perl core source
+(PERL_CORE is defined) or the Perl core extensions (PERL_EXT is
+defined). When compiling XS code outside of Perl core the wrapping
+does not take place. Note, however, that intermixing the _r-forms
+(as Perl compiled for multithreaded operation will do) and the _r-less
+forms is neither well-defined (inconsistent results, data corruption,
+or even crashes become more likely), nor is it very portable.
+
=head1 EXAMPLES
File C<RPC.xs>: Interface to some ONC+ RPC bind library functions.
https://perl5.git.perl.org / perl5.git / blobdiff