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From: ssb@quest.UUCP (Scott Bertilson)
Newsgroups: comp.sys.3b1
Subject: Re: MDG / ipcs on the on the 3b1
Summary: patch loadable driver with "adb"
Keywords: MDG shmem ipc
Message-ID: <1991Mar04.225630.14404@quest.UUCP>
Date: 4 Mar 91 22:56:30 GMT
References: <1991Feb28.182152.11622@cbnews.att.com>
Organization: Quest Research, Inc.
Lines: 29


  I had to solve a similar problem when trying to run Ander's Klemets'
version of the KA9Q NOS code.  He had modified it to use shared memory
and a number of semaphores.  In the "nipcs" or "lipcs" driver, there
are symbols:
	shminfo
	msginfo
	seminfo
which are structures declared in "<sys/shm.h>", "<sys/msg.h>",
and "<sys/sem.h>".  You can do:
	cd /etc/lddrv
	mv nipc.o nipc.o.orig && cp nipc.o.orig nipc.o
	adb -w nipc.o
	msginfo,6?D
	(find the value you want to change)
	msginfo+0xC?W 0t48
I haven't played (that I can remember) with increasing the system
maximum parameters, but I assume the structures are dynamically
allocated when the driver is loaded.  I do know that in the case
of semaphores I was able to increase the maximum per id to be
the same as the system-wide limit and it worked fine.
  You will have to reboot before the change takes effect.  You
must also (of course) be sure that "/etc/lddrv/drivers" includes
"nipc" so that driver is loaded.

-- 

Scott S. Bertilson   ...ssb@quest.UUCP
			scott@poincare.geom.umn.edu