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From: dstewart@fas.ri.cmu.edu (David B Stewart)
Newsgroups: comp.unix.wizards
Subject: Re: What new system calls do you want in BSD?
Message-ID: <7848@pt.cs.cmu.edu>
Date: 5 Feb 90 20:17:43 GMT
References: <12157@stealth.acf.nyu.edu>
Distribution: usa
Organization: Carnegie-Mellon University, CS/RI
Lines: 21

How about implementing good ol' semaphores, with a much simpler interface
than Sys V.  I've written a front end to Sys V semaphores (under SunOS x.x)
which give me the good old classical P() and V() operations.  
I don't need all that other stuff associated with Sys V.  Why not provide a 
simple system call, which works just as described in all those operating system 
textbooks.  The same goes with shared memory; if BSD 4.4 doesn't have 
lightweight processes with shared memory, then provide some sort of system call
to allow processes to establish shared memory segments.

Another useful call would be peek(address) which will return 1 if
address is legal within the processes address space, or 0 (i.e. error)
if a write/read operation to that address would cause a bus error or
segmentation fault.  I know that the SunOS kernel provides that routine,
but there is no way for the user to access it.

~dave
-- 
David B. Stewart, Dept. of Elec. & Comp. Engr., and The Robotics Institute, 
	Carnegie Mellon University,  email: stewart@faraday.ece.cmu.edu 
The following software is now available; ask me for details
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