I first want to clarify that there are WAY better ways to do this, but if you want to increment a global variable to detect a signal being caught this will do the trick. As Paul noted earlier you shouldn't be trying to do anything complicated in the signal handler itself.

our $sig;
$sig = 1;

$SIG{INT}  = sub {
     $sig++;
};

my $oldsig;
while (1) {
  if ($sig != $oldsig) {
   $control->removeMonitorPID($monitor->{PID});  #Execute the code ori
+ginally in the signal handler.
   $oldsig = $sig;
  }
  .... Run main loop, but make sure to poll the status of the global v
+ariable ....
}
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