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Path: utzoo!mnetor!uunet!husc6!mailrus!ames!sri-spam!rutgers!mtune!mtunx!whuts!homxb!mtuxo!rolls!doug!tim
From: tim@doug.UUCP (Tim J Ihde)
Newsgroups: comp.unix.xenix,comp.unix.microport,comp.sys.att
Subject: Re: IPC facilities (shared memory)
Message-ID: <521@doug.UUCP>
Date: 9 Mar 88 20:48:57 GMT
References: <335@mancol.UUCP>
Lines: 27
Keywords: IPC, shared memory, semaphores
Summary: IPC programs

In article <335@mancol.UUCP>, samperi@mancol.UUCP (Dominick Samperi) writes:
> Has anyone used the SCO Xenix IPC facilities? More generally, what kind
> of applications have the IPC facilities (on any System V machine) been
> used for? I haven't seen any applications programs that use them.

I've got a set of simple programs that I wrote to allow
shell scripts to interact via semaphores.  They provide for things
like mksem (create a semaphore), rmsem (remove a semaphore), p, and v.
This allows shells to safely access a resource.

While I originally developed these programs on System V, they compiled and
ran OK on Xenix, as I recall - although I probably didn't do any
extensive testing.  I'm sure processes blocked and waited when they
were supposed to.

As for other uses, I've used shared memory to hold frequently accessed
information (like a database schema or a passwd file).  I know the UN*FY
database uses shared memory for record locking.  I've also used messages
for detailed control of child processes.  These are all under System V,
I haven't tried this kind of thing under Xenix yet.

	tim
-- 
Tim J. Ihde					ihnp4!ctsmain!doug!tim
(201) 560-6808

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