I'm writing and XS perl extension that calls an underlying C function. The C function has prototype 'void fcn(char *output)' and 'output' is null terminated so it is a string. The problem is that I don't seem to be able to get perl to recognize where the end of the 'output' string is. Here is the 'CODE:' section of my .xs file: 
CODE:
{           
    RETVAL = NEWSV(0, 16);
    SvPOK_only(RETVAL);
    SvCUR_set(RETVAL, 16);
            
    fcn(SvPV(RETVAL, len));
    printf("string: %s  length: %d", RETVAL, len);
}

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If I make use of this code from perl, the length of the string is always 16 even if the C function returns a string has a NULL char at, say, position 8. Can anyone help me? What am I doing wrong?

Thanks!

--mbr

Edit kudra, 2002-08-17 Replaced pre tags

In reply to perl guts and the SvPV() macro by mbr

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