groupmanage(1) and user-administered groups ------------------------------------------- There is a program `groupmanage' installed on chiark, 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. 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 my intervention: the group name must have the form -, except that if 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 (though it can be renamed with my assistance). For more formal groups (for example, those corresponding to particular organisations, or which interact with system software eg mail delivery) I will usually create a the group myself on request (and need not heed these restrictions), and will often also 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. -- iwj 19.08.1998