#!/usr/local/bin/perl -w
use strict;

my @uptime = split //, `uptime`;
my ($to,$from,$subject) = ('mail@list.com','sys@admin.com','ALERT : reboot');

if ($uptime[2] > 1 ){

open(MAIL, "|/usr/sbin/sendmail -t");

print <<MAIL;
To: $to
From: $from 
Subject: $subject 


Server rebooted in the last 24 hours.

MAIL

close(MAIL);

}