groupmanage(1) and user-administered groups
-------------------------------------------

There is a program `groupmanage', with which users can create their
own groups and change their group membership.

For a synopsis of its usage, type `groupmanage'.

Each group managed by groupmanage has an entry in /etc/grouplist as
well as in /etc/group.  This contains the administrative information
which controls who may do what to the group, in the form:
 group:description:owner:manager1,manager2,manager3:home-directory
(as many or few managers as you like).  groupmanage will modify this
file as well as /etc/group

Each group has a single owner user.  The owner and managers are
allowed to add and delete managers and members; only the owner may
change the group title.  Note that being a manager doesn't
automatically make you a member of a group - you must use
groupmanage --add to do that, and then log in again to ensure that the
new membership affects your session.

There are some restrictions on groups created by users without
administrator intervention: in the default configuration the group
name must have the form <username>-<groupname>, except that if
<username> is more than 4 characters only the first 4 need be given.
All groups created by a user have that user's name in the title.  Any
one user may not create more than 5 groups for themselves.

All group names must be less than 8 characters long, and a group once
created can not easily be deleted because revoking access to a uid or
gid on unix is very hard.  Groups can be renamed with assistance from
the system administrator.

For more formal groups (for example, those corresponding to particular
organisations, or which interact with system software eg mail
delivery) should probably be created by the sysadmin on request and
need not heed these restrictions; it might also be useful to create a
home directory for shared files.

When working with shared files, you should not remove (and should
reinstate, if necessary) the setgid bit on the shared directories, and
leave your umask set to allow group write (the default is 002).
You'll then find that you're able to work in group filespace areas
without having to ask other users to chmod files, or having to type
incantations to switch between working on shared files and your
personal files.


userv-utils are
Copyright 1996-2013 Ian Jackson <ijackson@chiark.greenend.org.uk>
Copyright 1998 David Damerell <damerell@chiark.greenend.org.uk>
Copyright 1999,2003
   Chancellor Masters and Scholars of the University of Cambridge
Copyright 2010 Tony Finch <fanf@dotat.at>

All the utilities here are free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with userv-utils; if not, see http://www.gnu.org/licenses/.
