$exit_value   = $? >> 8;
   $signal_num   = $? & 127; # or 0x7f ...
   $dumped_core  = $? & 128; # or 0x80 ...

##</code><code>##

   $high_byte       = $? >> 8;
   $was_interrupted = $high_byte & 0x80;
   $status          = $high_byte & 0x7f;