Linux · Bash Scripting

You see conditions written as [ $a -eq 20 ] instead of test. What is the bracket form, and what silently-fatal mistake does it invite?

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More in Bash Scripting

Beyond just replaying a fixed command sequence, what capabilities make a bash script a real programming language rather than a glorified alias?

You wrote a script whose first line is #!/bin/bash. What is that line called, and what does the kernel actually do with it when you run the file?

Your script's shebang says #!/bin/sh instead of #!/bin/bash. On Debian and Ubuntu, why might a working script suddenly break under that shebang?

Inside a script, how do you reach the first argument the user typed on the command line, and why does this beat a plain alias?

You just wrote a new script file, but running ./myscript gives 'permission denied'. Which access bit is missing, and why does read access alone not fix it?

You're tired of typing ./ in front of your script every time. What has to be true so you can call it by bare name from anywhere, and where do you put it?

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