+sub relay_signal {
+ my ($pid, $signal) = @_;
+ kill $signal, $pid;
+ $SIG{$signal} = 'DEFAULT';
+ kill $signal, getpid ();
+}
+
+sub xsystem {
+ my ($pid) = fork;
+ if (!defined ($pid)) {
+ # Fork failed.
+ die "fork: $!\n";
+ } elsif (!$pid) {
+ # Running in child process.
+ exec (@_);
+ exit (1);
+ } else {
+ # Running in parent process.
+ local $SIG{INT} = sub { relay_signal ($pid, "INT"); };
+ local $SIG{TERM} = sub { relay_signal ($pid, "TERM"); };
+ waitpid ($pid, 0);
+ return $?;