Newsgroups: comp.lang.c
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: WANTED: do while no key pressed (in portable code)
Message-ID: <1989Mar28.165801.20618@utzoo.uucp>
Organization: U of Toronto Zoology
References: <22064@agate.BERKELEY.EDU> <16535@mimsy.UUCP> <796@vector.UUCP> <11119@pur-ee.UUCP>
Date: Tue, 28 Mar 89 16:58:01 GMT

In article <11119@pur-ee.UUCP> hankd@pur-ee.UUCP (Hank Dietz) writes:
>In v7, it was added as empty(fd) (actually read(fd,NULL,0)) to test if a
>char could be read without actually reading it...

Sorry, you are thinking of a V7 variant, not V7 as released.  NULL was a
valid buffer address in V7 and hence could not be used for such a test
(and was not -- I just checked our V7 sources).
-- 
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