[bash] expand a command in a shell

[melodie]

Reading a doc, seeing "expand the commands", I thought I don't know what "expanding a command" mean, though I probably do it currently without me knowing I do it. A search on the web brought that page which I want to share, as there are commands I never used in it:
http://linuxcommand.org/lc3_lts0080.php

such as:

Code: [Sélectionner]


[me@linuxbox me]$ echo D*
Desktop Documents


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[me@linuxbox me]$ echo $(($((5**2)) * 3))
75
or

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[me@linuxbox Photos]$ mkdir {2007..2009}-0{1..9} {2007..2009}-{10..12}

Expansion

Each time you type a command line and press the enter key, bash performs several processes upon the text before it carries out your command. We have seen a couple of cases of how a simple character sequence, for example “*”, can have a lot of meaning to the shell. The process that makes this happen is called expansion.

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