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Check for arguments and exit script if none

Terminal - Check for arguments and exit script if none
[ $# == 0 ] && echo "Please supply arguments and re-run." && exit 1
2011-11-30 15:04:21
User: robinsonaarond
Functions: echo exit
-3
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Check for arguments and exit script if none

In a script, exit with quoted error message and status 1 if no arguments were supplied.

Add to favourites | Report as malicious

Alternatives

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Terminal - Alternatives

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What others think

The $# is zero, not blank, when there are no args.

[ $# == 0 ] && echo "arg req'd" && exit 1

or

[ $# == 0 ] && { echo "arg req'd"; exit 1; }

I tend to use the curlies because it clearer if you're doing the opposite:

[ $# == 0 ] || { echo "no args allowed"; exit 1; }
Comment by splante 77 weeks and 3 days ago

Using $# == "" works just fine, as well as 0. The curly braces make it clearer, I suppose, but you might as well put it on multiple lines if you're going for clarity.

Comment by robinsonaarond 77 weeks and 2 days ago

Wow, I take that back; I could have sworn the "" worked a few weeks ago. Thanks for noting that; it's changed now.

Comment by robinsonaarond 77 weeks and 2 days ago

[ ! $# == 0 ] || echo "No args"

This works if no arguments are specified.

Comment by MrMuddle 77 weeks and 2 days ago

[ ! $# == 0 ] || { echo "Please supply arguments and re-run"; exit 1; }

Comment by MrMuddle 77 weeks and 2 days ago

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