Re: Bash script for wireless

[Johannes Zarl <isilmendil@gmx.net>]

Hi John,

> I know how to use grep etc. to find known bits of output, but not
> how to isolate arbitrary output, for example ESSID names.
> 
> Can anyone point me in the right direction?

I used this in one script of mine:

available_essids=`iwlist air0 scanning | grep "ESSID" | sed 's/.*"\(.*\)".*/\1/'`

As so often, sed is write-once-read-never, so I will try to explain;-)

After the grep the input to sed should look something like this:
<output of grep>
                    ESSID:"FOO"
                    ESSID:"BAR"
                    ESSID:"BAZ"
</output of grep>

sed will now extract the string inside the quotes:
<part1 '.*">                    ESSID:"</part1><grouped part1 '\(.*\)'>FOO</grouped part1><ungrouped part2 '".*'>"</ungrouped part2>
etc.

Well, maybe this is even more obfuscated, but at least I tried..

Cheers,
  Johannes