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I've directory called /home/vivek/scripts/daily with over 25 perl / shell / python scripts for managing daily tasks. One day for some weird reason my crond died and I did not noticed the incident for 2 days.

Now crond is started and I'd like to run all those scripts. Here is a quick for loop running all scripts in a directory called ~/scripts/daily/:

for s in ~/scripts/daily/*;do [ -x $s ] && $s || : ;done

Above script will run each and every executable script it finds in a directory.

Update: As pointed out by jeff (see below), you can use run-parts shell script for the same purpose:
$ run-parts ~/scripts/daily/*

Generally I use Perl and Shell script for automation or to make system administration easier for me. Python is an interpreted, interactive, object-oriented programming language that combines remarkable power with very clear syntax. Python runs on Windows, Linux/Unix, Mac OS X, OS/2, Amiga, Palm Handhelds, and Nokia mobile phones.

You can easily adopt Python to manage UNIX and Linux systems while incorporating concepts of good program design. Python is an easy-to-learn, open source scripting language that lets system administrators do their job more quickly. It can also make tasks more fun:

As a system administrator, you run across numerous challenges and problems. Managing users, disk space, processes, devices, and backups can cause many system administrators to lose their hair, good humor, or sanity. Shell scripts can help, but they often have frustrating limitations. This is where a full-featured scripting language, such as Python, can turn a tedious task into an easy and, dare I say it, fun one.

The examples in this article demonstrate different Python features that you can put to practical use. If you work through them, you'll be well on your way to understanding the power of Python.

=> Python for system administrators

When invoked without arguments, the date command displays the current date and time. Depending on the options specified, date will set the date and time or print it in a user defined way. I've seen many sysadmin writing perl scripts for calculating relative date such as yesterdays or tomorrows day. You can use GNU date command, which is designed to handle relative date calculation such as:

  • 1 Year
  • 2 Days
  • 2 Days ago
  • 5 Years

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Reading an IP address in shell script required many time. However, different Linux distribution stores IP address in different files. If you are looking to run script under different UNIX like OSes such as Solaris or FreeBSD then you need to use the ifconfig command. The ifconfig command is not just used to configure a network interface, but it can be use to obtained information such as network IP, netmask and much more.
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