Possible bug in the enabling the hosts on the personal iris

[Rob Warnock]

In article <1377 at babcock.cerc.wvu.wvnet.edu> smp at cerc.wvu.wvnet.edu
(Shailesh M. Potnis) writes:
+---------------
| 	I am having problems in disabling the access control on the personal
| iris machines.  If I give the command xhost + prior to xterm, the system comes
| back with the message that access control disabled.  If one tries to check the
| allowed hosts by the xhost command iris lists only the local host and the
| current machine.  One cannot display applications from remote servers on this
| display.  However if one has opened any applications like xterm prior to
| disabling the access control by the command xhost + then everything goes as
| per the book.
| 	What can be the reason for this inconsistancy?  and are there any
| fixes for this.
+---------------

The reason you see this behavior is that when the last client disconnects,
the X server resets itself, preparing for another login. This is consistent
with its normal use when "xdm" or some similar program is controlling top-
level logins. You *want* the server to reset so the next user to login doesn't
get any leftovers.

But under 3.3.2, still using getty/login/NeWS/etc., the X server is fooled into
thinking you've logged out each time it has no clients. What's happening is:

	1. You run "xhost +foo" or "xhost +".
	2. "xhost" connects to the X server, adds "foo" to the access list.
	3. "xhost" exits, having done its work.
	4. There are no more clients, so the X server resets the world,
	   including the access list.
	5. A subsequent "xhost" finds no foreign hosts enabled.

The same thing also happens if you try to run "xrdb" by itself to load some
resources, such as your ~/.Xdefaults. It works, but as soon as it exits, the
X server says, "o.k., he's logged out, reset everything", and the resources
disappear. Frustrating, as you've found out!  (Me, too!  ;-}  ;-}  )

This will be automatically fixed in Irix 4.0, which will use "xdm" for the
X session control, but in the meantime you can "fake it" by starting up a
long-lived X application (I run an "xclock") *before* running "xrdb" or xhost".


-Rob

-----
Rob Warnock, MS-1L/515		rpw3 at sgi.com		rpw3 at pei.com
Silicon Graphics, Inc.		(415)335-1673		Protocol Engines, Inc.
2011 N. Shoreline Blvd.
Mountain View, CA  94039-7311