[NMLUG] grep help

[havoc at harrisdev.com (havoc)]

Ed Heron wrote:
>  I'm writing a bash script that needs to check if a particular person is 
> in a specific group.
> 
>  I'm using:
> 
> if grep "^${group}:.*[:,]${user}[,$]" /etc/group >/dev/null ; then echo 
> "${user} is a member of ${group}" ; fi
> 
>  Unfortunately, if $user is last in the list it appears to be false.  If 
> I `grep "^${group}:.*[:,]${user}$" /etc/group` it succeeds.
> 
>  I don't use many regexp, am I missing something?

Looks like the square brackets are breaking '$' as a metacharacter. I 
used alternation instead, and got success:


for group in audio video; do for user in bigpig yvonne; do if \
grep "^$group:.*[:,]$user\(,\|$\)" /etc/group >/dev/null ; then echo \
"${user} is a member of ${group}" ; fi; done; done


Jody
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