[ This is just a pointer to a document, which you might find helpful]

Advanced Bash-Scripting Guide

A complete guide to shell scripting, using Bash

Mendel Cooper - Brindlesoft

thegrendel@theriver.com


This tutorial assumes no previous knowledge of scripting or programming, but
progresses rapidly toward an intermediate/advanced level of instruction
(...all the while sneaking in little snippets of UNIX wisdom and lore). It
serves as a textbook, a manual for self-study, and a reference and source
of knowledge on shell scripting techniques. The exercises and heavily-
commented examples invite active reader participation, under the premise that
the only way to really learn scripting is to write scripts.

The guide is availabe at http://www.linuxdoc.org/LDP/abs/

The latest update of this document, as an archived "tarball" including both
the SGML source and rendered HTML, may be downloaded from the author's home
site (http://personal.riverusers.com/~thegrendel/abs-guide-1.1.tar.gz). See
the change log for a revision history
(http://personal.riverusers.com/~thegrendel/Change.log).