From: Paul Winalski <paul.winalski@gmail.com>
To: Paul Ruizendaal <pnr@planet.nl>
Cc: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] v3 pipes
Date: Sat, 25 Apr 2020 13:54:42 -0400 [thread overview]
Message-ID: <CABH=_VRf5whh3QoM3x+h-cZSy1Dj6n-KWtLHGuZ7aJwJ2Y=A_w@mail.gmail.com> (raw)
In-Reply-To: <430B2F35-D250-499E-83F9-58D4C1764CE0@planet.nl>
On 4/25/20, Paul Ruizendaal <pnr@planet.nl> wrote:
>
> I just tried making both pipe ends readable+writeable in my “V6.5” kernel
> and that appears to work. It allows for bi-directional communication in a
> half-duplex sense (i.e communicating walky-talky style). The other benefit
> is using just one file descriptor, at a time when a process had just 15 to
> work with.
If both pipe ends are readable+writeable, you have the Unix equivalent
of VMS mailboxes. There's lots of opportunity for both deadlock and
livelock, and some "broken pipe" situations become difficult or
impossible to detect.
-Paul W.
next prev parent reply other threads:[~2020-04-25 17:55 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-25 11:14 Paul Ruizendaal
2020-04-25 17:54 ` Paul Winalski [this message]
-- strict thread matches above, loose matches on Subject: below --
2020-04-24 12:54 Doug McIlroy
2020-04-23 13:48 [TUHS] V3 pipes Paul Ruizendaal
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