[ Thanks to CowGirl for this link.
]
“The bash shell is available on many Linux and UNIX systems
today, and is a common default shell on Linux. In this tip you will
learn how to handle parameters and options in your bash scripts and
how to use the shell’s parameter expansions to check or modify
parameters. This article focuses on bash, and the examples were all
run on Linux systems with bash as the shell. However, the same
expansions are available in many other shells, such as ksh, ash, or
dash, and you may use them with these shells on other UNIX systems
or even environments such as Cygwin. This tip builds on the tools
covered in the earlier tip Linux tip: Bash test and comparison
functions…”