I always wondered how scripts passed variables beginning with a '-', i.e 'foo.sh -q', or 'tar -zxfv' and so on.

I knew that '$1' in bash takes the first extra variable sent at the shell, but that can be any sort of word, not specifically a '-' parameter. Does that make sense?

Anyway, it turns out you can use this neat getopts function like so, with a case statement. This way you can also output a 'usage' mini-manual when a variable that is unrecognised, is passed:

usage()
{
cat << EOF
usage: $0 -option
 
Use this script to rsync this to that :)

It's sad when this sort of thing makes me laugh:

11:09 < diveli> uptime
11:09 < poilu> 11:09:20 up 3 days, 16:18, 0 users, load average: 0.05, 0.08, 0.03

Magic invisible poilu! Hooray for my trusty irc bot :)

This is my Client web/database usage/bandwidth statistics script as mentioned in the Think Tank.

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