From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael A. Olson" <mao@sleepycat.com>
To: "Bas Valkema" <bvalkema@knowhowww.nl>
Cc: elix@sourceware.cygnus.com
Subject: Re: EL/IX spec review, status
Date: Tue, 18 Jan 2000 14:38:00 -0000
Message-id: <200001182238.OAA09832@triplerock.olsons.net>
References: <200001181915.LAA38490@triplerock.olsons.net> <00011813242902.02412@linux> <003401bf6202$1d610f20$0303a0c0@BAS>
X-SW-Source: 2000-q1/msg00004.html

At 11:19 PM 1/18/00 +0100, you wrote:

> Sure, but what would be the difference between level 3 & 4 if the change is
> conducted? (sorry had no time to study the spec carefully.. ;-)

Level 4 right now has a bunch of system call interfaces not in
level 3.  They include:

	setuid/setgid
	process group support
	filesystem-based mutex support
	password and group database operations
	semaphores
	mapped memory
	shared memory
	some non-standard stream support
	popen() and friends
	named interfaces (if_nametoindex and friends)
	pty and raw terminal support
	common signal handling functions
	interfaces to spawn and manage processes

and just a couple of others.  The spec claims that the difference
between 3 and 4 is that 3 is multi-process and 4 is full Linux.
My argument is that shared memory is a useful abstraction for
multi-process, and belongs there.

The rest of the level 4 interfaces look right to me, based on
the designed differences between 3 and 4.

					mike