In shell scripts you can use $1 to refer to the first argument, $2 for the second, etc. If you want to refer to all arguments (e.g. when writing a bash script that takes an arbitrary amount of arguments and passes them on to another call), you may not want to do a “$1 $2 $3 $4 ...”.

Use $@ instead, like in this script:
$ cat welcome
#!/bin/bash
echo Hello to $@

When called, the above would produce this:
$ ./welcome the world and universe
Hello to the world and universe

Note that $@ works for both sh and bash.

Arne Hartherz

makandra.com

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Last edit

2012-08-17

License

Source code in this card is licensed under the MIT License.

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Posted by Arne Hartherz to makandra dev (2011-07-01 13:28)

Linux: Refer to all arguments of a script call

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