The Uses of Cron Tabs

By Hans Christian Tesch

Those who are familiar with Greek methodology will no doubt know Cronus who was the father of the Olympian gods. Kronus in Greek and roman times means time and thus here we get the words chronometer and chronology. Therefore cron tabs in programmer lingo means something tat deals with time.

Cron tabs are mostly seen in server side applications particularly in open source systems such as Red Hat and Linux systems. The subroutine command of the cron tab is set and used for timed routines or tasks that the server does on a regular basis. That is it acts like a timer for a certain procedure to be done at a set time during the day.

Thus this tab can have several subroutines within it. Cron tab is basically a short cut for Cron Table wherein certain tasks are assigned. Many benefits of these tabs are seen when used in terms of scheduling certain tasks at inopportune times of the day, which can be on holidays and ungodly hours of the night.

The Benefits

The benefits of this type of server side programming are numerous. For example, part of your services entails that you send an email to your subscribers updating them on certain information for the day and reminders and such every 3 am in the morning. Thus you can do two things.

First you can set your alarm clock at 3 am in the morning and manually send these emails one by one to your subscribers. Definitely this is not a very attractive proposition. The other thing you can do is to set a cron tab in your server to do this for you while you sleep at that time.

The tab in this case will set into a gear a process that will automatically send emails to everyone in your client list for as many times as you want for the next day, next month or even the next few years! The cron tab will do the most necessary routine things for you just in case you forget to do them.

You can also use the command in conjunction with other disk operating commands such as erase and delete. For example you may want to delete members from your site or forum that have lapsed a minimum on-line period, that is they have become inactive and thus you can purge them. So say that forum members will be expelled if they have a lapse of 1 week of posting or logging in, this command can do it for you automatically without you having to do it manually.

How to activate

The cron tab can be activated in your server just by looking for a cron tab icon in the control panel. It is just a matter of clicking on it and adding the timed commands that you need. You can do this for the most routine of tasks whether deleting or sending mail and others. You can also set a frequency for this to do daily, weekly, monthly or even annually. The choice is entirely up to you.