Yum's additional tools

I've learnt new helpful commands recently that belongs to yum tools (thank you MLLR). I'd like to say a few words about the usage of the commands.

Script to inform about new updates in CentOS

A couple days ago I shared my script for OpenSuSE. Now I've re-written that Perl script to speak the language of yum. The script below is intended to run periodically by cron and to send me an e-mail, if new updates have been found for the system. It's nothing extraordinary, yum-cron can this too. But an advantage of my Perl script is that the e-mail is sent only once. No email is sent, if the same updates are found again. The trick is that the Perl script saves the updates (if any) in a temporary file to compare its content then with the updates found at the current run.

Besides I wanted to see the installed and the available versions of a package side by side. I could unfortunately get this output with yum or repoquery directly.