Screen user suggestions please.. What do screen users do when they add a new group? How to create a BSD newgrp command?

[Colin Leath <cleath_(_at_)_experienceartist_(_dot_)_org>]

About a month later I have run into this problem again, and assume there
must be some solution.

I've just made a CVS repository following the instructions at
http://cvsbook.red-bean.com/cvsbook.html#The%20Cederqvist%20Manual 
(relevant parts printed below). Basically, I created a new group, and I
need to be recognized as being in that group in order to use cvs.

I am logged in 11 times using a screen session, and would like to be able
to use cvs in each of these windows, should I feel like it.

Apparently, I will have to stop all my work, terminate the screen session,
restart screen, reconfigure the various screen windows (tailing logs and
so on).

This is little different from having to reboot!

a sort of work-around I have found is:
> screen tcsh -l 
> login

but then I lose all my screen environment variables.

Any suggestions you have are welcome. I could have restarted &
reconfigured my screen session by now, but no doubt I will encounter this
problem again.

Thanks!

Colin
please cc: cleath_(_at_)_j9k_(_dot_)_com .. I just read the mailing list on the web.

--------------------------
In my research (e.g. searching for newgrp and bsd on google) I find things
like this:
http://www.enteract.com/~enf/lore/unix/bsd/4.2-user-changes.html
 
o    The  group  identifier  notion  has  been extended to a
     ``group set''.  When users log in to  the  system  they
     are  placed in all their groups.  Access control is now
     done based on the group set rather than just  a  single
     group  id.   This  has obviated the need for the newgrp
     command.

-or-

4.1.3.3 Groups and BSD or SVR4 UNIX

   One of the many enhancements that the Berkeley group made to the UNIX
   operating system was to allow users to reside in more than one group
   at a time. When a user logs in to a Berkeley UNIX system, the program
   /bin/login scans the entire /etc/group file and places the user into
   all of the groups in which that user is listed.[6] The user is also
   placed in the primary group listed in the user's /etc/passwd file
   entry. When the system needs to determine access rights to something
   based on the user's membership in a group, it checks all the current
   groups for the user to determine if that access should be granted (or
   denied).

   Thus, Berkeley and SVR4 UNIX have no obvious need for the newgrp
   command - indeed, many of the versions do not include it. However,
   there may be a need for it in some cases. If you have a group entry
   with no users listed but a valid password field, you might want to
   have some users run the newgrp program to enter that group. This
   action will be logged in the audit files, and can be used for
   accounting or activity tracking. However, situations where you might
   want to use this are likely to be rare. Note, however, that some
   systems, including AIX, do not support use of a password in the
   /etc/group file, although they may allow use of the newgrp command to
   change primary group.
 

-------------------------
1. Add a Unix group cvs to your system. Any users who need to access
       the repository should be in this group. For example, here's the
       relevant line from my machine's /etc/group file:
cvs:*:105:kfogel,sussman,jimb,noel,lefty,fitz,craig,anonymous,jrandom
    2. Make the repository's group ownership and permissions reflect this
       new group:
floss$ cd /usr/local/newrepos
floss$ chgrp -R cvs .
floss$ chmod ug+rwx . CVSROOT


On Sun, 1 Oct 2000, rich wrote:

> nope. GID's are loaded only at login time and never again.
> Sorry...
> 
> -----Original Message-----
> From: owner-misc_(_at_)_openbsd_(_dot_)_org [mailto:owner-misc_(_at_)_openbsd_(_dot_)_org]On Behalf Of
> Colin Leath
> Sent: Sunday, October 01, 2000 7:59 PM
> To: misc_(_at_)_openbsd_(_dot_)_org
> Subject: How make change in group membership affect currently logged on
> users?
> 
> 
> I created a new group using groupadd and added a user to it by editing the
> /etc/groups file. The problem is that this change in group membership is
> not affecting currently logged in users.
> 
> Is there any way to have a change in group status take effect for a user
> without having the user have to re-login? The newgrp command on Linux
> appears to make this possible. Is there a method applicable to BSD?
> 
> Here is some more detail:
> 
> # groups myusername
> 
> immediately recognized the new group membership, however, if the _user_
> runs the groups command it does not show the new group, until s/he logs
> out and logs back on.
> 
> I have a user session that has been logged in this whole time that cannot
> create files in a directory owned by the group to which the user has been
> added.
> 
> A more recent user session (for the same user) _is_ able to create files
> in that directory.
> 
> If there is a better place to be asking this question, please point me to
> it.
> 
> thanks,
> Colin