[helper-method]

Nicely written tutorial. The only thing I would suggest is always prefering [[ to [ because it makes dealing with parameter expansions much more easier. Also [[ is most likely as shell builtin, in contrast to [, which is most likely an external program.

[lutusp]

> The only thing I would suggest is always prefering [[ to [ because it makes dealing with parameter expansions much more easier.

I wrote the article before Bash 3 was released, and the article remains appropriate for platforms that don't have Bash 3 abilities. If you read down in the article, you will see where I address this issue:

http://arachnoid.com/linux/shell_programming.html#Bash_Versi...