June 2000
Beginner
704 pages
14h 55m
English
Content preview from Practical Linux
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Using Shell Variables
Variables are temporary placeholders for information, either numbers or sequences of characters (called strings). The system (that is, the shell) has a number of useful predefined variables, such as the user name, home directory, and system name. Using the env command generates a listing of all persistent environment variables (meaning that they don't stop existing when the current command or script ends, instead they exist for your Linux login environment as a whole) defined in your shell. Listing 21.3 is the output generated by the env command on my machine. This will vary somewhat from machine to machine, of course.
Code Listing 21.3. Sample Output Listing of the env Command
[jwalter@jansmachine samples_22]$ env USERNAME= ... |
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.