[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference bulova::decw_jan-89_to_nov-90

Title:	DECWINDOWS 26-JAN-89 to 29-NOV-90
Notice:	See 1639.0 for VMS V5.3 kit; 2043.0 for 5.4 IFT kit
Moderator:	STAR::VATNE

Created:	Mon Oct 30 1989
Last Modified:	Mon Dec 31 1990
Last Successful Update:	Fri Jun 06 1997
Number of topics:	3726
Total number of notes:	19516

3374.0. "One application, multiple displays, and X$X0 " by CSC32::K_TICE (Ada...Keeping the world safe for bureaucracy!) Fri Sep 21 1990 16:45

Hello all,

I have a question concerning one client application program with connections 
to multiple display servers.

PROBLEM:

   Sometimes, DECnet X$X0 links are created even though a call
   XOpenDisplay fails. I was able to reproduce this by running a
   program that attempted to do calls to XOpenDisplay in a loop. 

   Each time I tried to open a display on the same server.  On said
   server, I customized sucurity so as to DISALLOW access for the
   client program in question. 

   As you would expect, the calls to XOpen display are not
   successful.  However, if I run NCP and do a "SHOW KNOWN LINKS
   WITH NODE xxxx", I see that each attempt at opening a display
   create a NEW X$X0 link, even though the XOpenDisplay failed! 

   I have already read DECWINDOWS NOTES 19, 26, 1196, and 2985.


QUESTIONS:

   1. Is the above expected and/or known behavior?

   2. Is there a way to get rid of these superfluous links (with out 
      exiting the image)?

   3. Is there a way to query the server to ask it "Are you there, 
      and can I establish a connection with you?" other than just 
      trying to do an XOpenDisplay and seeing what happens?


   4. Is there a way to recover from an X IO error?  (mostly 
      rhetorical ... see DECWINDOWS note 876)



Thanks for any insight!

Ken

T.R	Title	User	Personal Name	Date	Lines
3374.1	QAR orphaned DECnet links	STAR::ORGOVAN	Vince Orgovan	`Sat Sep 22 1990 14:46`	2
	If DECnet logical links are hanging around after XOpenDisplay reports a open failure, that is indeed a bug. Please file a QAR.
3374.2	Thanks ...any more ideas?	CSC32::K_TICE	Ada...Keeping the world safe for bureaucracy!	`Mon Sep 24 1990 11:26`	12
	RE: .1 I will submit an SPR (rather than QAR; customer problem). Any ideas on a a way around "seeing if a server can accept a connection" ? Thanks, Ken
3374.3	...and a way to get rid of excess links?	CSC32::K_TICE	Ada...Keeping the world safe for bureaucracy!	`Mon Sep 24 1990 11:28`	5
	...almost forgot. Is there a programatic way to get rid of these DECnet links that han around? Ken
3374.4		MIPSBX::thomas	The Code Warrior	`Mon Sep 24 1990 19:43`	2
	DO a ncp show known link status. What state are the links in?
3374.5	Link status is "DI receive"	CSC32::K_TICE	Ada...Keeping the world safe for bureaucracy!	`Fri Sep 28 1990 12:16`	12
	RE -.1 Sorry it took so lonk for me to get back. As I said above, the link status (State) is DI receive I am not a network weenie, so I am not sure if this tells you anything useful or not (?!). Ken