display an embeded help message from bash script header

[ "$1" == "--help" ] && { sed -n -e '/^# Usage:/,/^$/ s/^# \?//p' < $0; exit; }
With this one liner you can easily output a standard help message using the following convention: Usage: is the start marker Stop at the last #
Sample Output
#!/bin/bash
#
# Usage: do someting really funny
#  --help      This message
#  --force     force be stronger
#  --remove    delete whatyou've done, be CAREFULL
#
# ex:  myfun  dosomething
#
# myfun --force dosomething_REALLY_DO_IT
#

[ "$1" == "--help" ] && { sed -n -e '/^# Usage:/,/^$/ s/^# \?//p' < $0; exit; }

echo really funny !

9
By: syladmin
2009-09-04 20:36:06
sed

What Others Think

Why didn't I think of that? Elegant.
sufoo · 520 weeks and 1 day ago
This is pickier, but shorter: [ "$1" == "--help" ] && \ awk '/^#: / { print $0 }' $0 Start your help message with "#:". Also convenient for embedding other messages in scripts.
lbonanomi · 519 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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