How I learned to stop worrying and love the Cron.
Today, in our ongoing series on learning to live with Linux's ``inner dæmons'', we are going to look at two dæmons that schedule job execution on Linux. These dæmons are more or less exactly like those found on virtually every UNIX out there. (Linux has separate dæmons for at and cron. Old versions of Linux used a program called ``atrun'', which was run in root's crontab once a minute to execute at requests. Some other Unix operating systems have atd functionality directly in crond. This qualifier brought to you by the bureau of auctorial honesty. This article will cover atd and crond as they are distributed with most currently sold distributions, including Debian 2.1, Red Hat, SuSE and Corel, among others.) My test cases were all carried out on a Red Hat 6.1 installation using version 3.1.7 of at. Debian and SuSE versions I currently have are at 3.1.8.