If you know the name of a scalar variable, you can get a pointer to its SV
by using the following:
- SV* get_sv("package::varname", FALSE);
+ SV* get_sv("package::varname", 0);
This returns NULL if the variable does not exist.
If you know the name of an array variable, you can get a pointer to its AV
by using the following:
- AV* get_av("package::varname", FALSE);
+ AV* get_av("package::varname", 0);
This returns NULL if the variable does not exist.
SVt_PVGV Glob (possible a file handle)
SVt_PVMG Blessed or Magical Scalar
- See the sv.h header file for more details.
+See the F<sv.h> header file for more details.
=head2 Blessed References and Class Objects
To create a new Perl variable with an undef value which can be accessed from
your Perl script, use the following routines, depending on the variable type.
- SV* get_sv("package::varname", TRUE);
- AV* get_av("package::varname", TRUE);
+ SV* get_sv("package::varname", GV_ADD);
+ AV* get_av("package::varname", GV_ADD);
HV* get_hv("package::varname", GV_ADD);
Notice the use of TRUE as the second parameter. The new variable can now
extern int dberror;
extern char *dberror_list;
- SV* sv = get_sv("dberror", TRUE);
+ SV* sv = get_sv("dberror", GV_ADD);
sv_setiv(sv, (IV) dberror);
sv_setpv(sv, dberror_list[dberror]);
SvIOK_on(sv);
This MGVTBL structure is set at compile-time in F<perl.h> and there are
-currently 19 types (or 21 with overloading turned on). These different
-structures contain pointers to various routines that perform additional
-actions depending on which function is being called.
+currently 32 types. These different structures contain pointers to various
+routines that perform additional actions depending on which function is
+being called.
Function pointer Action taken
---------------- ------------
e PERL_MAGIC_envelem vtbl_envelem %ENV hash element
f PERL_MAGIC_fm vtbl_fm Formline ('compiled' format)
g PERL_MAGIC_regex_global vtbl_mglob m//g target / study()ed string
- H PERL_MAGIC_hints vtbl_sig %^H hash
+ H PERL_MAGIC_hints vtbl_hints %^H hash
h PERL_MAGIC_hintselem vtbl_hintselem %^H hash element
I PERL_MAGIC_isa vtbl_isa @ISA array
i PERL_MAGIC_isaelem vtbl_isaelem @ISA array element