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Re: standard error codes

From BartC <bc@freeuk.com>
Newsgroups comp.lang.c
Subject Re: standard error codes
Date 2017-01-09 22:36 +0000
Organization A noiseless patient Spider
Message-ID <o51362$bse$1@dont-email.me> (permalink)
References (2 earlier) <bf564370-cac4-4030-8487-893c5ea71ddc@googlegroups.com> <86260b21-0fa2-42b4-93c6-08e9241d4c17@googlegroups.com> <lnk2a4qi1v.fsf@kst-u.example.com> <64011b84-2f8d-44f2-902a-0eacfcdf630b@googlegroups.com> <o510fi$16v$1@dont-email.me>

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On 09/01/2017 21:50, BartC wrote:

> C's zero-based indexing makes it harder to use 0 for failure and N for
> success.
>
> For example, for a routine that searches an array indexed 0 to N-1 for
> the index of some value, 0 must be one of the return values denoting
> success. With a one-based list, then you can't do:
>
>   if (find(A,N,X)) ...

I mean you can't use this for zero-based arrays as you can for 
one-based. It's just another range of applications where using 0 to 
conveniently signal failure can't used, and that means thinking up some 
other scheme, that can't be quite as simple or intuitive.

Another example is strcmp(), where you have to remember to compare 
against 0 to ensure two strings are the same, or two blocks of bytes are 
the same when using memcmp, as there is no streq or memeq. And you don't 
always remember...

-- 
bartc

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Thread

standard  error codes Thiago Adams <thiago.adams@gmail.com> - 2017-01-08 06:34 -0800
  Re: standard  error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-08 11:05 -0800
    Re: standard  error codes Thiago Adams <thiago.adams@gmail.com> - 2017-01-09 03:33 -0800
      Re: standard  error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-09 04:55 -0800
        Re: standard  error codes Keith Thompson <kst-u@mib.org> - 2017-01-09 09:06 -0800
          Re: standard  error codes Thiago Adams <thiago.adams@gmail.com> - 2017-01-09 09:52 -0800
            Re: standard error codes BartC <bc@freeuk.com> - 2017-01-09 21:50 +0000
              Re: standard error codes BartC <bc@freeuk.com> - 2017-01-09 22:36 +0000
                Re: standard error codes supercat@casperkitty.com - 2017-01-09 14:51 -0800
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-09 23:39 +0000
                Re: standard error codes supercat@casperkitty.com - 2017-01-09 15:51 -0800
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-09 16:08 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-09 18:51 -0800
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-10 02:02 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-10 07:34 -0800
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-10 01:39 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-10 09:07 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-10 09:59 -0800
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-10 12:02 -0800
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-10 12:53 -0800
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-10 13:03 -0800
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-10 15:41 -0800
                Re: standard error codes Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-11 02:56 +0000
                Re: standard error codes supercat@casperkitty.com - 2017-01-11 07:42 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-10 12:59 -0800
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-10 18:14 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-10 12:12 -0800
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-10 20:35 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-10 13:00 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-11 08:16 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 18:25 +0000
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-11 19:09 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-11 12:03 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 20:10 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-11 12:19 -0800
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-11 20:31 +0000
                Re: standard error codes Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2017-01-11 15:32 -0500
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 20:48 +0000
                Re: standard error codes Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2017-01-11 15:58 -0500
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-11 13:01 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 21:05 +0000
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-11 21:08 +0000
                Re: standard error codes Gareth Owen <gwowen@gmail.com> - 2017-01-11 21:38 +0000
                Re: standard error codes BartC <bc@freeuk.com> - 2017-01-11 21:58 +0000
                Re: standard error codes David Brown <david.brown@hesbynett.no> - 2017-01-12 12:11 +0100
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-12 09:28 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-12 18:06 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-12 11:39 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-12 19:50 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-12 13:03 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-12 21:13 +0000
                Re: standard error codes <william@wilbur.25thandClement.com> - 2017-01-12 20:00 -0800
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-13 01:56 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-13 12:54 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-13 09:35 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-13 17:38 +0000
                Re: standard error codes James Kuyper <jameskuyper@verizon.net> - 2017-01-13 13:06 -0500
                Re: standard error codes raltbos@xs4all.nl (Richard Bos) - 2017-01-18 12:00 +0000
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-18 12:13 +0000
                Re: standard error codes Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-12 16:43 -0800
                Re: standard error codes <william@wilbur.25thandClement.com> - 2017-01-12 19:34 -0800
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-13 09:27 -0800
                Re: standard error codes raltbos@xs4all.nl (Richard Bos) - 2017-01-12 19:33 +0000
                Re: standard error codes Keith Thompson <kst-u@mib.org> - 2017-01-12 12:10 -0800
                Re: standard error codes supercat@casperkitty.com - 2017-01-11 11:50 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 20:38 +0000
                Re: standard error codes jadill33@gmail.com - 2017-01-11 12:26 -0800
                Re: standard error codes Richard Heathfield <rjh@cpax.org.uk> - 2017-01-11 20:44 +0000
      Re: standard  error codes Keith Thompson <kst-u@mib.org> - 2017-01-09 09:03 -0800
  Re: standard  error codes supercat@casperkitty.com - 2017-01-08 11:40 -0800

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