Re: Accessing variables from inside a C-XS

Hi Josef,

 > I'd like to access a Perl-variable (a scalar) from within an XS. I do
 > accept that the scalar may not (yet) exists, so I'd cater for that:
 >
 > How do I do that:
 > - find out if a scalar exists
 > - access the contents of the scalar.

If you know the name of a scalar variable, you can get a pointer to its 
SV by using the following:

     SV*  perl_get_sv("package::varname", FALSE);

This returns NULL if the variable does not exist.

If you want to know if this variable (or any other SV) is actually 
defined, you can call:

     SvOK(SV*)

http://www.sdsc.edu/~moreland/courses/IntroPerl/docs/manual/pod/perlguts.html

Hope this helps.

Cheers,
Olli