Pro Bash: Learn to Script and Program the GNU/Linux Shell

© The Author(s), under exclusive license to APress Media, LLC, part of Springer Nature 2023

J. VarmaPro Bash https://doi.org/10.1007/978-1-4842-9588-5_5

5. Parameters and Variables

Jayant Varma¹  

(1)

Berwick, VIC, Australia

 

Variables have been part of the Unix shell since its inception more than 30 years ago, but their features have grown over the years. The standard Unix shell now has parameter expansions that perform sophisticated manipulations on their contents. bash adds even more expansion capabilities as well as indexed and associative arrays.

This chapter covers what we can do with variables and parameters, including their scope. In other words, after a variable has been defined, where can its value be accessed? This chapter gives a glimpse ...