[LUNI] adding user to a group?

[Ronald Petty]

If I add a user to a group, is there a way to make a process that is
currently running under the user (when the process started was not in
that group) use the new group info so the running process can get
access?

file one (owned by group X)
process one (owned by user a)

a is not in group x (assume 770 for permissions, so a cannot read x
group files)

If I add a to group x, he should be able to read them, however if the
process is already running it doesn't seem to let that process.

Help the blind please :)  (I know I can start a new shell and login, but
is there another way).

Ron