I've C library with function expecting char* param which must be NULL in some cases. I wish to use it from perl this way: 
c_func(undef); # NULL param
c_func('');    # empty string param
c_func(123);   # string '123' param
c_func('qwe'); # string 'qwe' param

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Current XS realization: 

void
c_func(param)
    char *    param = SvOK(ST(0)) ? SvPV_nolen(ST(0)) : NULL;

[download]

This task sounds like standard opration, so is there exists simpler way, without ugly "SvOK ? SvPV_nolen : NULL" chain?

In reply to XS: SvOK ? SvPV_nolen : NULL by powerman

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