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From: pfalstad@phoenix.princeton.edu (Paul Falstad)
Newsgroups: comp.unix.shell
Subject: Re: co-processes and bash (ksh does it, can bash?)
Message-ID: <52206@wookumz.gnu.ai.Princeton.EDU>
Date: 27 Jun 91 07:10:42 GMT
References: <LARRY.91Jun26103254@mitra.mitra.com>
Sender: gnus@idunno.Princeton.EDU
Organization: League For Fighting Chartered Accountancy
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larry@mitra.mitra.com (Larry Williamson) wrote:
>Ksh supports the concept of a co-process. You can start a process in
>the background with it's stdin and stdout connected to the shell. You
>do this by putting the |& operator after the command. You can then use
>read -p to read from the co-process and print -p to write to it.
>
>I don't see any mention of this nice feature in the BASH
>documentation.

Hmm.  zsh supports this, using a slightly different syntax.  You
use the "coproc" keyword instead of |&, and use >&p or <&p instead
of -p.  I'd probably use process substitution instead, though, to
open a pipe to or from a process.  The coproc stuff wasn't tested very
well because I couldn't really think of a good use for it.

--
Paul Falstad                     | 10 PRINT "PRINCETON CS"
pfalstad@phoenix.princeton.edu   | 20 GOTO 10