%typemap(in) (unsigned char *string1) {
   $1 = (unsigned char *)SvPV_nolen($input);
}

##</code><code>##

%typemap(out) (unsigned char *output,  const size_t output_length)
{
          $result = newSVpv((char *)$1, $2);
          sv_2mortal($result);
          argvi++;
          delete $1;
}