Yesterday a 20 line shell script caught a race condition in one of software I work on. Our best engineers looked at the problem, a vendor case was filed, and there was thoughts of automatically restarted the application to fix the issue at hand.

In the end, a 20 line shell script to strace for file operations continuously provided the needed visibility into the issue at hand.

Update: The shell script.

The shell script itself, though trivial, is owned by the company I work for, but the basic concept was as follows:

#!/bin/bash

nixcraft has a link on how to read a file line by line. The method is a great way to read a file, but there some trouble spots I thought I would point out.

In the script, the special variable IFS is set:

# set the Internal Field Separator to a pipe symbol
IFS='|'

The tells the read command to split “cyberciti.biz|74.86.48.99″ into “cyberciti.biz” and “74.86.48.99″ and thus fill both the domain and ip variables here:

Today I want to discuss splitting strings into tokens or “words”. I previously discussed how to do this with the IFS variable and promised a more in depth discussion. Today, I will make the case on WHY to use IFS to split strings as opposed to using a subshell combined with awk or cut.

A guide for beginning Linux if you have no experience and no knowledge whatsoever. Written in response to an article on the BBC website. Which is very negative about Linux, because the writer didn't know how to find information about a very strange thing he was trying.

Want to make your linux desktop look like a mac? This is a tool which helps in the process.
If you want to see a full howto go to howtoforge:

http://www.howtoforge.com/mac4lin_make_linux_look_like_a_mac

Or go directly to it's download page: