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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

2218.0. "Shared memory or Unix Domain socket transport" by IOUONE::BRYSON () Tue Feb 06 1990 13:28

Someone once told me (I guess it was the infamous "THEY") that the :0 designation
for the display under Ultrix uses shared memory.  I was looking at the server 
process and I saw no SYSV shared memory being used.  Is there such a thing as 
a shared memory transport for Ultrix as found on VMS?   If not was is the 
difference between the following designations?

	:0
	local:0
	unix:0

Thanks,

David
T.RTitleUserPersonal
Name		DateLines
2218.1FLUME::dikeTue Feb 06 1990 17:118
unix:0 uses Unix domain sockets for transport.  That's what are in your 
/tmp/.X11-unix directory.  I think both :0 and local:0 are shared memory 
transport.

I did an ipcs -m -a on my PMAX and it showed 5 shared memory segments which 
are owned by the X server.  How did you determine that your server doesn't use
shared memory?
				Jeff
2218.2Maybe on PMAX's only??IOUONE::BRYSONFri Feb 09 1990 13:467
I used both ipcs and my own utility which monitors process information and
no shared memory is attached to the server or the client.  I am on a VS3200.

OK, so the PMAX uses shared memory for :0 syntax.  Do you think this means
that :0 and unix:0 on a VAX are the same -- unix domain sockets??

David
2218.3FLUME::dikeFri Feb 09 1990 17:335
I don't know.  You could test it by taking your host name and localhost out
of your host file, setting your DISPLAY variable to :0 and see if you can
run X things.  If you can, then Xlib is going though unix domain sockets, and
if you can't then it is going over inet sockets.
				Jeff