A function to handle timing out

timeout.pl

#!/usr/bin/perl

use strict;
use warnings;

sub timeout {
	my ($wait, $code, $timedout, $error) = (@_, 
		sub { warn $@ }, sub { die $@ });

	eval {
		local $SIG{ALRM} = sub { die "timeout\n" };
		alarm $wait;
		$code->();
		alarm 0;
		1;
	} or do {
		alarm 0; #ensure that alarm is not still set
		#raise error if it isn't a timeout
		if ($@ eq "timeout\n") {
			$timedout->();
		} else {
			$error->();
		}
	};
}

timeout 1, 
	sub { die "oops\n"         },
	sub { warn "timeout out\n" },
	sub { warn "died with $@"  };

timeout 1,
	sub { select undef, undef, undef, 2 },
	sub { warn "timeout out\n"          },
	sub { warn "died with $@"           };

timeout 1,
	sub { print "normal execution\n" },
	sub { warn "timeout out\n"       },
	sub { warn "died with $@"        };

timeout 1, sub { select undef, undef, undef, 2 };
timeout 1, sub { die "and here it ends" };

print "this is not printed\n";