Problem printing on tie()'d filehandle from XSUB

[Steve Hay]

Hi,

I have a module that prints to STDERR after that filehandle has been 
tie()'d to a simple package that captures everything written to it.  
When I "print STDERR" from a Perl sub the output is captured as 
expected, but when I "fprintf(stderr, ...)" from an XSUB the output is 
not captured and appears in the Console window instead.

It occurred to me that fprintf(stderr, ...) is probably wrong - it 
should really be PerlIO_printf(PerlIO_stderr(), ...) shouldn't it?  
However, the output is still not captured after doing that

How do I get the tie() magic applied to the filehandle when it is used 
within the XSUB, or can't I do that?

Thanks,

Steve