[SOLVED] Setting a variable

henrtm05 · 09-27-2010, 11:56 PM

This is from a previous post

here is a link to the previous post. http://www.linuxquestions.org/questi...ommand-834518/

I am trying to set this command to a variable, I think it is not working because I am running a command within a command.

This is the command

grep "\:`grep ^mygroup /etc/group | cut -d: -f3`\:" /etc/passwd

I tried doing

fristgrp=`grep "\:`grep ^mygroup /etc/group | cut -d: -f3`\:" /etc/passwd`

but it just hangs and does nothing.

Any help would be appreciated thanks.

prayag_pjs · 09-28-2010, 12:19 AM

Hi If i am not wrong you want to grep the output of :

Quote:

grep ^mygroup /etc/group | cut -d: -f3

Suppose that group is root;then

Quote:

grep ^root /etc/group | cut -d: -f3

; will give output

Quote:

0

Now if you grep 0

Quote:

grep 0 /etc/passwd

it gives output;

Quote:

root:x:0:0:root:/root:/bin/bash
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
operator:x:11:0

perator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
mysql:x:27:480:MySQL Server:/var/lib/mysql:/bin/bash
qemu:x:107:107:qemu user:/:/sbin/nologin
smolt:x:490:474:Smolt:/usr/share/smolt:/sbin/nologin

i.e it lists all 0 like 107;480 etc.

What i am trying to say is if your group id is 111 then it will give even 1, 12 or 32 or 212 etc

So change the way you are using commands;better write script!

evo2 · 09-28-2010, 12:24 AM

Nesting backticks "`" will not work. Also I don't think you should escape the colons.

Does the following work?

Code:

fristgrp=$(grep ":$(grep ^mygroup /etc/group |cut -d: -f3):" /etc/passwd)
echo $fristgrp

Evo2.

henrtm05 · 09-28-2010, 01:18 AM

This worked for me thanks.