Subject: Re: one more xdm problem
To: None <skippy@macro.Stanford.EDU>
From: maximum entropy <>
List: port-pmax
Date: 01/29/1999 23:53:54
>Date: Fri, 29 Jan 1999 20:05:15 -0800 (PST)
>From: Bill Studenmund <skippy@macro.Stanford.EDU>
>On Fri, 29 Jan 1999, maximum entropy wrote:
>> I believe you're also mistaken here, unless something has changed
>> in the past year to make this necessary.  The only pmax of mine that
>> uses xdm is running 1.3.0 and works just fine with the console enabled
>> in /etc/ttys.
>You're lucky! If you have the getty enabled on the tty at the same time as
>xdm, you get into race conditions. Whichever of the two opens the console
>first wins. I had such a problem w/ an ultrix box once. You log in via
>xdm, do things, logout, and get a command line prompt! Ick!

Can you actually reproduce this problem on NetBSD/pmax, or are you

Looking at the /etc/rc script, I see that xdm is not started
asynchronously.  If it so happens that xdm opens the console before
daemonizing itself, it's going to win the race every time.  If the
correct process is guaranteed to win the race every time, it isn't a
race condition.

Additionally, xdm does not exit when you log out of the X session, so
the "race" would stay won even after logging out.

I don't have an xsrc tree handy to verify my guess as to how this
works.  But I do have reason to believe that it does work, and I don't
think I'm just lucky.


entropy -- it's not just a good idea, it's the second law.