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_4

4. Command-Line Parsing and Expansion

Jayant Varma¹  

(1)

Berwick, VIC, Australia

 

One of the things that shell programming language does is the parsing of command-line arguments and the expansion it performs on words in the line. Let us look in detail what happens when a command is called with arguments, what does the shell do before it invokes the command.

To help visualize what happens, we can use the short script as seen in Listing 4-1 called sa, which will display what the shell has passed to it after processing all of the arguments. Each argument is printed on a separate line, preceded by the ...