Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!well!ewhac
From: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab)
Newsgroups: comp.sys.amiga
Subject: Re: IPC - A proposal
Message-ID: <5532@well.UUCP>
Date: 25 Mar 88 22:01:17 GMT
References: <5375@well.UUCP> <5377@well.UUCP> <2609@pdn.UUCP>
Reply-To: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab)
Organization: onhigh!oracle
Lines: 50
Keywords: IPC PIPES SOCKETS QUEUES SEMAPHORES

In article <2609@pdn.UUCP> reese@pdnbah.UUCP (Don Reese) writes:
>In article <5377@well.UUCP> ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) writes:
>>	UNIX achieves IPC (usually) through pipes.  One program's stdout is
>>connected to another program's stdin.  On UNIX, this works great since, in
>>most cases, all user I/O through the program is through stdin and stdout.
>>
>What do you consider a pipe?  Unix provides many methods of interprocess
>communications.  Here is a list of the more widely used methods:
>	Pipe:	[ ... ]

	This is how most *users* accomplish IPC under UNIX.  They say:

% foo | bar | baz | bletch | grep 'slime-mold' | lpr

	And it works.  Unfortunately, it won't work for the majority of
Amiga programs, since their user interfaces are, by and large, not driven by
stdin and stdout.  They're driven by gadgets, menus, requesters, mouse
movements, etc.  The console.device does try and translate some of this
stuff into escape sequences, but there's just too much stuff here.  Ordinary
UNIX-style pipes are extraordinarily useful, but they are nowhere near the
general solution we're looking for.

>	Named Pipe:  [ ... ]

	Same problems, but still useful.

>	Queues:	[ ... ]

	You're getting warm....

>	Sockets: [ ... ]

	Now you're cookin'.  Now all we need is a standard of command and
data transfer.  Not even UNIX has this yet, largely because they've gotten
along so well with piping stdin and stdout all over the place for so long.
This isn't a drawback; the fact that UNIX only *really* supports ASCII
terminals has been a great advantage, making IPC relatively easy for them.
However, visually oriented systems will require a more general solution.

	I wonder how Sun did it with SunTools, if they did it at all?

>	Semaphores and Shared Memory:  [ ... ]

	The current Exec message and semaphore facilities fulfill this
aspect nicely, I feel.

_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
Leo L. Schwab -- The Guy in The Cape	ihnp4!ptsfa -\
 \_ -_		Recumbent Bikes:	      dual ---> !{well,unicom}!ewhac
O----^o	      The Only Way To Fly.	      hplabs / (pronounced "AE-wack")
"Work FOR?  I don't work FOR anybody!  I'm just having fun."  -- The Doctor