SvROK (scalar value reference OK/true) will tell you if your SV is a reference; not whether is simply exists - in this case, the value returned by ST(1), which should be the second value off the stack.

You might want to look at the actually type of reference SvROK thinks is coming back from the ST(1) call.

That can be done with: 

  /* if SvROK(ST(1) is true, i.e. it's a reference */
  printf("\nDEBUG: Type is %d\n",SvTYPE(SvRV(ST(1)));

[download]
Take a look in sv.h for specifics on the meaning of the individual return value.

See also: perlguts, perlxs, perlxstut

Hope that helped,
-v
"Perl. There is no substitute."

In reply to Re: Help needed for XS on Perl v5.8.3 by Velaki
in thread Help needed for XS on Perl v5.8.3 by pijush

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