Debian, string in string.

Shell Programming and Scripting
1

Example, check if user is in a group.

echo groups
Berty adm, dialout, cdrom, foo, foo

how to check that 'dialout' is in that output

I thought of awk '{print $x}' but x won't aways be the same.

Thanks.

2

I am assuming

has values

Berty adm, dialout, cdrom, foo, foo

a simple grep should get you

echo $groups |  grep dialout

with awk

echo $groups | awk '/dialout/{ print $0 }'
3

With shell builtins:

case $groups in (*dialout*) echo "true";; esac

This is not precise though. Like the "grep" in the previous post. (The latter can be improved with "grep -w".)

4

Using an interim variable:

ngroups=${groups#* }                                         # remove the prefix
[[ ,${ngroups// /}, == *,dialout,* ]] && echo yes || echo no # remove all other spaces; add , to beginning & end

You can use if instead of the && ... || construct I used above. Or you can put it in MadeInGermany's case statement:

case ,${ngroups// /}, in (*,dialout,*) echo "true";; esac

Andrew