This works for me under Fedora 14:

# groups USERNAME
USERNAME : USERNAME GROUPNAME

# usermod -G $(id -Gn USERNAME | sed "s/GROUPNAME//g" | sed "s/ /,/g" | sed
"s/,,/,/g" | sed "s/,$//g") USERNAME

# groups USERNAME
USERNAME : USERNAME


--- On Sun, 12/12/10, Joachim Schipper <joachim@joachimschipper.nl> wrote:

From: Joachim Schipper <joachim@joachimschipper.nl>
Subject: Re: remove users from group
To: misc@openbsd.org
Date: Sunday, December 12, 2010, 1:22 PM

On Sun, Dec 12, 2010 at 03:44:18PM +0400, OpenBSD Geek wrote:
quoted text
> To remove users from example group "users", i usually do it by editing the
> file /etc/group, and remove it manually.
> Is there a way from command line to remove some users from a specific
> group ?
>
> I want to do a script like that :
>
> list="1 2 3 4 5 6"
> for i in $list
> do
> usermod -G wheel, staff username$i
> done
>
> This will add username[1-6] to group wheel and staff, but how can i do
> like this script to remove them in staff group without editing the file
> /etc/group ?

Do some light scripting with an appropriate utility, e.g. userinfo(8).

        Joachim

--
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