#####################
#
sub display
# display a message using xmessage
# execs the xmessage command using the "double-fork trick" to prevent zombies
{
my $msg = shift;
my $child;
my $buttons='Roger:0';

if($child = fork)
	{ #running in parent
	warn("parent: pid $$ is waiting on child $child\n") if $debug;
	waitpid($child,0);	# wait for first child
	warn("parent: pid $$ is returning from spawn()\n") if $debug;
	return;
	}
	else
	{ # running in child -- fork again to protect against zombies
	if(0 != fork)
		{ #running in zombie-protector parent
		warn("first child: pid $$ exiting now\n") if $debug;
		exit(0);
		}
		else
		{ #running in zombie-protected child
		warn("second child: pid $$ is execing the command\n") if $debug;
		open(XMESS,"|xmessage -xrm 'xmessage*Title:Notify' -buttons '$buttons' -file -")
			|| die("$prog: xmessage failed:$!\n");
		(print XMESS $msg) || die("$prog: xmessage didn't work:$!\n");
		exit(0);
		}
	}
die("spawn: you're not supposed to run this.\n");
}