my $rcvd = 0 ;     # added counter for signals seen in eval's handler

  sub wrap_sigs {
...
    eval {
      for my $sig (keys %$signals) {
        $old_sighandlers{$sig} = ($SIG{$sig} || 'DEFAULT');
        $SIG{$sig} =  sub { $rcvd++ ; die ("SIG $sig $rcvd\n") };
...