How can I make bash recognise that some user has been added to a group?

jschiwal · 09-19-2007, 12:54 AM

During the VirtualBox installation. The instructions in the dialog even say that you need to logout after adding yourself to the vboxusers group.

archtoad6 · 09-19-2007, 12:17 PM

Does anyone disagree that logging in is the key act to getting a newly added group recognized? It does not matter whether you want this group recognized w/in a tty, Xterm, Desktop Environment, or Window Manager -- you must log in after being added to a group in order to exercise that group's privileges.
No one knows if there is way to "reload" the /etc/group info. w/o logging out & logging back in. This is analogous to daemons, e.g. dnsmasq, that can be made to reload their config files w/o having to be shut down & restarted, let alone needing a full re-boot of the whole OS.
OP, myself, & others find this very inconvenient.

Bernard Swiss · 09-20-2007, 01:48 AM

I'd say that's an excellent summary.

archtoad6 · 09-20-2007, 05:10 AM

Now, can anyone give us a solution, or explain why one is not possible? And I mean impossible, as opposed to not available or not convenient.

JZL240I-U · 09-21-2007, 08:10 AM

Well, I can't as I'm no expert. I just have that nagging suspicion, that it is possible.

Here http://www.tldp.org/LDP/abs/html/system.html there is something about "newgrp" and "chgrp". Possibly more about the .bashrc(s) can be found in the rest of the manual.

Probably a stupid question: Did you try to "export $GROUPS" so that the new groups is made available system wide, or is that a different mechanism...?

archtoad6 · 09-23-2007, 08:25 AM

Although I included "tty, Xterm" in my summary for the sake of completeness, the real problem, at least for me, is w/ the GUI's, where logging out & back in is real problem: time consuming & the risks losing session info -- what web pages & what files are open in which work spaces -- that sort of thing, not to mention losing unsaved data.

We have discussed some relatively painless solutions for tty's & Xterm's. My favorite is "[sudo] su <current_user>". I believe it does not pass the current command history through; however, that can be cured by (a preceding) "history -w".

I don't use screen, so I have no idea what its problems w/ new groups might be. Given that it allows more complicated tty/Xterm sessions, this might be analogous to the GUI problem.

FWIW, I don't think that exporting $GROUPS will work, because it gets its info from /etc/group at log in.