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From: jfc@athena.mit.edu (John F Carr)
Newsgroups: comp.lang.c
Subject: Re: getchar and EOF (was: One more point regarding = and == (more flamage))
Message-ID: <1991Apr8.222824.24474@athena.mit.edu>
Date: 8 Apr 91 22:28:24 GMT
References: <1991Apr4.215605.2801@syssoft.com> <1991Apr7.064003.8552@athena.mit.edu> <3043@cirrusl.UUCP>
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In article <3043@cirrusl.UUCP>
	dhesi%cirrusl@oliveb.ATC.olivetti.com (Rahul Dhesi) writes:

>I have always assumed that EOF is guaranteed to be -1.  I think there
>is enough history behind EOF == -1 (just as with NULL == 0) that it
>isn't likely to be anything else.

The ANSI standard says EOF is a negative number.  It does not have to be -1.
If I ever write a C implementation which doesn't need to be binary
compatible with an existing UNIX library, I'll make EOF something like -256
to make sure it can never equal a signed or unsigned char value.
Traditionally, EOF is -1.  I don't know what POSIX says.

--
    John Carr (jfc@athena.mit.edu)