Hello gurus-

I have been wracking my brain with this one, and can't get it to perform quite how I want it to. My goal is to have a script that runs a system call and if it receives a SIGINT (CTRL+C), kill the system call along with the pl script. Here is an oversimplified example: 
$SIG{INT}=\&myhand;

print "Parent pid = $$ \n";
$pid = open(CMD, "ping google.com -n 15 |");
print "Ping running... pid = $pid \n\n";

# uncommenting this line breaks ability to SIGINT
#print <CMD>;

# keep the script running; only the SIGINT will exit
while (1){sleep 1};

sub myhand() {
  print "Parent $$ caught SIGINT.\n";
  print "Parent $$ will KILL $pid.\n";

  kill 9, $pid;
  exit(0);
}

[download]
The script works fine to kill the ping until you uncomment the print. Then it will not accept the SIGINT until the ping has completed.

It seems like this would be a pretty common request. I know that system() calls will ignore SIGINT. Am I making this too complicated, or not complicated enough? I even tried with fork(), but I don’t think I am doing it properly: 

#parent
if ($forkpid = fork) {
  local $SIG{INT} = sub { print "i'm quitting"; kill 9, $pid; exit; };
  waitpid($forkpid, 0);

#child
} else {
  die "cannot fork: $!" unless defined $forkpid;
  $SIG{INT} = sub { print "i'm quitting child"; close(CMD); kill 9, $p
+id; exit; };
  $pid = open(CMD, "ping google.com -n 15 |");
#  exec ("ping google.com -n 15") or die "Can't exec: $!\n";
}

print "Done with fork.  Here are my results:";
print <CMD>;

[download]
I seem to have the same problem if I use open(). If I use exec(), it looks like the ping command itself accepts the CTRL+C?

I would be extremely appreciative of any assistance you could offer!

In reply to SIGINT and system calls by Anonymous Monk

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