Given the following:

    neelix hgs 100 %> ps -o pid,pgid,time,args -u hgs
      PID  PGID        TIME COMMAND
            [...]
      995   995 12-19:04:35 /usr/local/bin/ruby -w ./pso_test.rb

Then:

    neelix hgs 101 %> /usr/bin/nohup -g -Fa 995
    nohup: cannot control process 995

Why not?  I had this on another ruby process as well.
Is it something to do with Ruby?

What I expected was the process group including the children to be
"nohup"ed.  The nohup man page does suggest using `ps -o sid` to find
the process to nohup, but that is a session leader, not a process
group, and it also seems to be the login shell. Since the whole
point of this is to allow me to logout, while leaving these things
running, nohupping the login shell seems wrong to me.

I've not used this side of nohup before, and I'm having a job
understand the setsid man page.  Can anyone tell me why this
behaviour is correct, or whether it isn't?

This is with Ruby 1.6.7 on Solaris 9.

        Thank you
        Hugh