From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Awk or Limbo ?
From: geoff.9fans@collyer.net
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Message-Id: <20010427191000.3ABBA19A80@mail.cse.psu.edu>
Date: Fri, 27 Apr 2001 15:09:41 -0400
Topicbox-Message-UUID: 95906de0-eac9-11e9-9e20-41e7f4b1d025

For writing some applications, limbo is quite pleasant.  I've written
concurrent ("multithreaded") programs in limbo and felt comfortable
doing so, whereas using the Unix LWP (light-weight process) libraries
(or POSIX threads) directly has always seemed hazardous.  Unix LWPs
are fighting Unix, specifically the libraries, that were designed
assuming one process (or "thread") per address space.  This is one
reason (aside from unportability across Unixes and dubious gains) that
we let Rich Salz go off and do INN; I had no desire to deal with that
mess, especially the mess 10 years ago.

However, limbo is implemented as a part of Inferno and the two are
somewhat intertwined, so running limbo programs on Plan 9 is really
running limbo programs in Inferno on Plan 9, and Inferno's interface
as a command (emu) to the surrounding Plan 9 isn't seemless, though
it's getting better.  Thus forsyth's recent comments about a native
implementation of limbo on Plan9, which would make it more appealing
for some jobs.

libthread attempts to capture some of the benefits of limbo (notably
communication) in C, but I'd rather have one kind of process (not
processes and threads) and it feels a little like LWP libraries to me,
plus you don't get the concise limbo communication syntax and
automatic memory (de)allocation.