hash ref to & from C

bgiii has asked for the wisdom of the Perl Monks concerning the following question:

I have an embedded Perl app where I generate a hash reference in perl and pass this back to C. If I print the hex address in both Perl and C, I get the same number.

I don't intend to use the pointer in C, just pass it around as an opaque pointer.

My question is how to get this void * from C back into Perl so that I can access the contents of this hash reference. Now I can push simple stuff onto the stack, but what I need to be able to do is push this hash reference address on the stack such that when I call this Perl code via call_pv, I can access this perl function (for instance):

sub foo {
  my ($href, $key) = @_;
  print $href->{$key};
}

Thanks a bunch. This is a hard one to google for... WGIII

Comment on hash ref to & from C

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Re: hash ref to & from C by dave_the_m (Monsignor) on Sep 10, 2005 at 13:06 UTC
something like: `void call_foo(HV* hash, SV* key) { dSP; PUSHMARK(SP); XPUSHs(hash); XPUSHs(key); PUTBACK; (void) call_pv("foo", G_VOID); SPAGAIN ; }` [download] See perlcall for more details Dave.	[reply] [d/l]
Re: hash ref to & from C by samtregar (Abbot) on Sep 10, 2005 at 20:00 UTC
The Perl man-pages are good but I recommend you pick up a copy of Extending and Embedding Perl. It is far and away the best reference for the C side of Perl programming. -sam	[reply]