Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!cs.utexas.edu!asuvax!mcdphx!mcdchg!chinet!les
From: les@chinet.chi.il.us (Leslie Mikesell)
Newsgroups: comp.unix.wizards
Subject: Re: pty bugs & features
Message-ID: <1990Aug29.153306.18173@chinet.chi.il.us>
Date: 29 Aug 90 15:33:06 GMT
References: <3948@auspex.auspex.com> <6038@muffin.cme.nist.gov> <13650@smoke.BRL.MIL>
Organization: Chinet - Chicago Public Access UNIX
Lines: 18

In article <13650@smoke.BRL.MIL> gwyn@smoke.BRL.MIL (Doug Gwyn) writes:
>In article <6038@muffin.cme.nist.gov> libes@cme.nist.gov (Don Libes) writes:
>>Why do pty's return EIO instead of 0 upon EOF?

>If they do this, it is clearly wrong and would most likely be due to
>UNIX development now being done, or at least directed, by people who
>don't understand UNIX.  read() should not return -1 upon encountering
>normal EOF on ANY object.

Is this meant to imply that the developers of STREAMS don't understand
unix?  A read on a STREAMS file is documented to return -1 when O_NDELAY
is set and there is no data available (which has unfortunately been
propagated into the tty emulation of at least some network implimentations).
Apparently there is some reason to want to know about zero length
messages.

Les Mikesell
  les@chinet.chi.il.us