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From: doug@cs.dartmouth.edu (Doug McIlroy)
Subject: [TUHS] Excise process from a pipe
Date: Thu, 10 Jul 2014 08:04:43 -0400	[thread overview]
Message-ID: <201407101204.s6AC4hKQ026601@coolidge.cs.dartmouth.edu> (raw)
In-Reply-To: <20140710045223.GA19076@www.oztivo.net>

In the suggested answer, the code changes but the process survives.

I suspect the answer to my original question is no, but I know only a tiny
fraction of the cumulative API of the extended Unix family.

Doug

>> Was there ever a
>> flavor of Unix in which a process could excise itself
>> from a pipeline without breaking the pipeline?
>
> If in the middle of a pipeline, all I can think of is:
>
>       close fd 0 and fd 1
>       dup() read end of pipe 1 to be stdin (fd 0)
>       dup() write end of pipe 2 to be stdout (fd 1)
>       exec("/bin/cat")



  parent reply	other threads:[~2014-07-10 12:04 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-10  2:49 [TUHS] Subject:unpipeIt'seasy for a process to insert a new process intoapipelineeither upstream or down unpipe Doug McIlroy
2014-07-10  4:52 ` [TUHS] Excise process from a pipe Warren Toomey
2014-07-10  5:00   ` Dave Horsfall
2014-07-10  5:06   ` Christopher Vance
2014-07-10  8:43     ` Warren Toomey
2014-07-10 12:03   ` Doug McIlroy
2014-07-10 12:04   ` Doug McIlroy [this message]
2014-07-10 14:45     ` Larry McVoy
2014-07-10 15:10 Noel Chiappa
2014-07-10 15:11 ` Larry McVoy
2014-07-10 16:06 Noel Chiappa
2014-07-10 16:04 ` Larry McVoy
2014-07-10 16:12 Noel Chiappa
2014-07-14 14:13 Doug McIlroy
2014-07-14 15:12 Noel Chiappa
2014-07-16 21:31 Noel Chiappa
2014-07-17 15:42 Noel Chiappa
2014-07-18 15:33 Noel Chiappa

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