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From: allbery@ncoast.UUCP (Brandon Allbery)
Newsgroups: comp.unix.xenix,comp.unix.microport,comp.unix.wizards
Subject: Re: IPC facilities (shared memory)
Message-ID: <7541@ncoast.UUCP>
Date: 23 Mar 88 22:37:20 GMT
References: <335@mancol.UUCP> <9844@steinmetz.steinmetz.UUCP> <150@marob.MASA.COM> <9947@steinmetz.steinmetz.UUCP>
Reply-To: allbery@ncoast.UUCP (Brandon Allbery)
Followup-To: comp.unix.xenix
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 28

As quoted from <9947@steinmetz.steinmetz.UUCP> by davidsen@steinmetz.steinmetz.UUCP (William E. Davidsen Jr):
+---------------
| In article <150@marob.MASA.COM> samperi@marob.UUCP (Dominick Samperi) writes:
> (statement that processes don't inherit shm segments after fork() in SysV)
| | Perhaps you are talking about the Xenix-style IPC facilities here
| 	See original posting... I said SysV and meant it.
| | (sgget, etc.) which I no nothing about.  When the SysV-style facilities
| | are used a forked child process must attach a shared memory segment
| 	Not true!
+---------------

From the manual page for fork(2), System V Release 2:

"...the child process inherits the following attributes from the parent
process:

	...
	all attached shared memory segments
	..."

I'll check the Xenix manuals at work tomorrow and see what they say, but
remember that Xenix 5 is schizoid about shared memory... no telling from
my end whether System V shared memory is implemented in terms of Xenix shared
data or vice versa or if they're separate facilities (but they *do* share a
global pte table, according to the Xenix V/386 manual at work!).
-- 
	      Brandon S. Allbery, moderator of comp.sources.misc
       {well!hoptoad,uunet!hnsurg3,cbosgd,sun!mandrill}!ncoast!allbery