From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon,  8 May 2000 00:34:11 -0400
From: Russ Cox rsc@plan9.bell-labs.com
Subject: [9fans] Plan 9 future (Was: Re: Are the Infernospaces gone?)
Topicbox-Message-UUID: a7f0e0f6-eac8-11e9-9e20-41e7f4b1d025
Message-ID: <20000508043411.9q7Y6rRpvK1VbERxXrz0ZmOoOF3fviVGNd6e7KNPCT0@z>

  >only 3 substantial programmes written in Alef - acme, rio and the IP stack. The
  >IP stack found its way back into the kernel and the other two were converted to
  >use a new thread library.

  Does this mean Plan 9 peoples abandoned concurrent programming, and
  joined to the ordinal threading scheme?  I'd like to know the reason...

Concurrent programming is alive as ever,
but is accomplished via a thread library for
C that provides most of Alef's functionality
(procs, tasks, buffered and unbuffered channels).

The benefits are that there need not be
two copies of each library now, and the programs
are more easily portable to other architectures
(there was no Alef compiler for the 68000, for
instance) as well as other operating systems
(the thread library has been ported to Linux).

The drawbacks are you lose type checking
on channel communication and a little bit of
syntactic sugar.  They're not particularly
noticeable in practice.

Russ