SVt_PVAV Array
SVt_PVHV Hash
SVt_PVCV Code
- SVt_PVGV Glob (possible a file handle)
+ SVt_PVGV Glob (possibly a file handle)
SVt_PVMG Blessed or Magical Scalar
See the F<sv.h> header file for more details.
For more information, consult L<perlxs> and L<perlxstut>.
+=head2 Autoloading with XSUBs
+
+If an AUTOLOAD routine is an XSUB, as with Perl subroutines, Perl puts the
+fully-qualified name of the autoloaded subroutine in the $AUTOLOAD variable
+of the XSUB's package.
+
+But it also puts the same information in certain fields of the XSUB itself:
+
+ HV *stash = CvSTASH(cv);
+ const char *subname = SvPVX(cv);
+ STRLEN name_length = SvCUR(cv); /* in bytes */
+ U32 is_utf8 = SvUTF8(cv);
+
+C<SvPVX(cv)> contains just the sub name itself, not including the package.
+For an AUTOLOAD routine in UNIVERSAL or one of its superclasses,
+C<CvSTASH(cv)> returns NULL during a method call on a nonexistent package.
+
+B<Note>: Setting $AUTOLOAD stopped working in 5.6.1, which did not support
+XS AUTOLOAD subs at all. Perl 5.8.0 introduced the use of fields in the
+XSUB itself. Perl 5.16.0 restored the setting of $AUTOLOAD. If you need
+to support 5.8-5.14, use the XSUB's fields.
+
=head2 Calling Perl Routines from within C Programs
There are four routines that can be used to call a Perl subroutine from