K&R, 2nd edition, Brian's concerns with ``char c = EOF''

From	Meredith Montgomery <mmontgomery@levado.to>
Newsgroups	comp.lang.c
Subject	K&R, 2nd edition, Brian's concerns with ``char c = EOF''
Date	2021-11-19 15:57 -0300
Organization	Aioe.org NNTP Server
Message-ID	<86pmqwkm7u.fsf@levado.to> (permalink)

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I did not get Brian Kernighan's concern with setting EOF to a char c.
The context is

  char c = getchar();

And Kernighan says:

--8<---------------cut here---------------start------------->8---
We must declare c to be a type big enough to hold any value that getchar
returns. We can't use char since c must be big enough to hold EOF in
addition to any possible char . Therefore we use int.
--8<---------------cut here---------------end--------------->8---

I'm trying to justify this using C99's document.  Here's what I find.

--8<---------------cut here---------------start------------->8---
Section 6.25 Types
[...]

3. An object declared as type char is large enough to store any member
of the basic execution character set. If a member of the basic execution
character set is stored in a char object, its value is guaranteed to be
positive.  If any other character is stored in a char object, the
resulting value is implementation-defined but shall be within the range
of values that can be represented in that type.
--8<---------------cut here---------------end--------------->8---

So I can't be sure a char would always be signed, for example.  I can't
be sure EOF would fit in a char.

Am I looking at the right place, thinking the right thing?  Thank you.

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K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Meredith Montgomery <mmontgomery@levado.to> - 2021-11-19 15:57 -0300
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-19 12:21 -0800
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Meredith Montgomery <mmontgomery@levado.to> - 2021-11-19 18:14 -0300
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-19 14:10 -0800
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Meredith Montgomery <mmontgomery@levado.to> - 2021-11-20 17:30 -0300
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' scott@slp53.sl.home (Scott Lurndal) - 2021-11-21 16:01 +0000
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Philipp Klaus Krause <pkk@spth.de> - 2021-11-22 11:23 +0100
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-22 12:55 -0800
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Philipp Klaus Krause <pkk@spth.de> - 2021-11-23 17:04 +0100
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-23 09:43 -0800
            Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Philipp Klaus Krause <pkk@spth.de> - 2021-11-24 11:26 +0100
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-10 01:41 -0800
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' David Brown <david.brown@hesbynett.no> - 2021-12-10 14:40 +0100
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Barry Schwarz <schwarzb@delq.com> - 2021-11-19 12:22 -0800
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Meredith Montgomery <mmontgomery@levado.to> - 2021-11-19 18:10 -0300
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' David Brown <david.brown@hesbynett.no> - 2021-11-20 13:24 +0100
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Meredith Montgomery <mmontgomery@levado.to> - 2021-11-20 17:32 -0300
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Mark Bluemel <mark.bluemel@gmail.com> - 2021-11-22 00:27 -0800
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Mark Bluemel <mark.bluemel@gmail.com> - 2021-11-22 00:34 -0800
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-22 02:04 -0800
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Mark Bluemel <mark.bluemel@gmail.com> - 2021-11-22 02:46 -0800
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-11-22 21:22 -0800
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-11-22 22:03 -0800
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' scott@slp53.sl.home (Scott Lurndal) - 2021-11-23 14:52 +0000
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-11-26 07:31 -0800
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-08 07:26 -0800
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-08 12:16 -0800
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-08 18:59 -0800
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-08 19:23 -0800
            Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-09 06:30 -0800
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Manfred <noname@add.invalid> - 2021-12-09 16:10 +0100
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-09 16:05 +0000
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Bart <bc@freeuk.com> - 2021-12-09 17:41 +0000
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-09 12:24 -0800
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-09 22:59 +0000
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-09 21:26 +0000
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Bart <bc@freeuk.com> - 2021-12-09 22:37 +0000
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-09 23:09 +0000
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-10 01:58 -0800
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-10 10:46 -0800
                Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-12 08:21 -0800
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Paul <nospam@needed.invalid> - 2021-12-09 10:31 -0500
            Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-09 13:32 -0800
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' luser droog <luser.droog@gmail.com> - 2021-12-09 17:08 -0800
            Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-10 12:45 -0800
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Manfred <noname@add.invalid> - 2021-12-11 19:17 +0100
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Bart <bc@freeuk.com> - 2021-12-11 23:19 +0000
              Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-15 00:31 -0800
      Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Mark Bluemel <mark.bluemel@gmail.com> - 2021-12-09 02:26 -0800
        Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Bart <bc@freeuk.com> - 2021-12-09 11:20 +0000
          Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Dave Dunfield <dave.dunfield@gmail.com> - 2021-12-09 06:50 -0800
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Andrey Tarasevich <andreytarasevich@hotmail.com> - 2021-12-08 20:00 -0800
  Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' Kaz Kylheku <480-992-1380@kylheku.com> - 2021-12-12 18:55 +0000
    Re: K&R, 2nd edition, Brian's concerns with ``char c = EOF'' James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-12-12 14:38 -0500

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