Russ's solution solves most popular case that arises in human group
working.
However allowing chgrp without editing /adm/users will solve
different problem.
Suppose bob is a teacher and he is teaching something to alice and
carol.
Alice want to show her files to only bob, and carol also want to show
her files only to bob.
How to do that ?
Creating new group does not answer the purpose.
The only solution of current Plan 9 is
chgrp bob ...
by host owner.
There is another solution.
Bob can create a directory, say /bob/submit,
and make it group bob and mode 777.
Then alice and carol can each run
mkdir /bob/submit/$user
chmod 770 /bob/submit/$user
and put their files in that new directory,
which is owned by them but has group bob.
Russ
