Perl timed child process

timer.pl

#!/usr/bin/perl -w

use strict;
use POSIX;

my $MAX_EXEC_TIME = 10;
my $pid;

eval {
    local $SIG{'ALRM'} = sub { die "timed out\n" };
    alarm($MAX_EXEC_TIME);
    print "Starting child process\n";
    $pid = fork();
    if ($pid) {
        print "Child Pid = $pid\n";
        waitpid $pid, 0;
    }
    else {
        my $limit = 5;
        my $cont = 0;
        while ($cont <= $limit){
            print("Doing work for $cont/$limit seconds\n");
            sleep(1);
            $cont ++;
        }
        exit 0;
    }
};

if ($@) {
    if ($@ eq "timed out\n") {
        print "I timed out and killed pid $pid\n"; 
        if ($pid) {
            kill(15, $pid);
        }
        $pid = undef;
        }   
    else {
        print "something else happened: $@\n";
        }   
    }   
else {
    print "Child process terminated as expected. I can keep going...\n";
}