Path: utzoo!attcan!uunet!anise!apple!bloom-beacon!EXPO.LCS.MIT.EDU!jim
From: jim@EXPO.LCS.MIT.EDU (Jim Fulton)
Newsgroups: comp.windows.x
Subject: Re: Xdm and NCD X-terminal
Message-ID: <8908311842.AA28037@expo.lcs.mit.edu>
Date: 31 Aug 89 18:42:08 GMT
References: <239@lib.tmc.edu>
Sender: daemon@bloom-beacon.MIT.EDU
Organization: X Consortium, MIT Laboratory for Computer Science
Lines: 19



        I am using a NCD X-terminal...
        ...if I switch off the X terminal and then back on, xdm fails
        to provide me with a login prompt.

    If I may speak on NCD's behalf, this is a known problem with the NCD box.

It isn't fair to call it a "problem with the NCD box" and to make
it sound like they have done something wrong.  If there is no traffic on
a TCP connection, then there is no way for the host side to recognize that
the terminal has been turned on and then turned off.  Doing periodic XSyncs
and retrying to open the connection will take care of this, but you end up
trading wasted cycles for activation time when the terminal is turned on.

The long term solution, which is being worked on by a number of people, is
the XDM Control Protocol.  This provides a way for terminals and display
managers to communicate so that turning the terminal off and on will work 
nicely.