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Re: what is the best way

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Keith Thompson wrote:
> Les Cargill <lcargill99@comcast.com> writes:
> [...]
>> - Have this basic structure:
>>
>> thing.h:
>>
>> #ifndef _THING_H_
>> #define _THING_H_ 1
>> ...
>> #endif
>>
>> guarding all header files.
> [...]
>
> Identifiers starting with an underscore and an uppercase letter
> (or with two underscores) are reserved to the implementation for
> any use; in other words, you should never use such identifiers in
> your own code.
>
> Just use this:
>
> #ifndef THING_H
> #define THING_H
> ...
> #endif /* THING_H */
>
> (or some scheme that maps reasonably well from file names to
> identifiers without stepping on anything that's reserved).
>


Excellent point. I *always* forget that. Apologies for the noise;
I simply meant "use guards on your header files."


> Note that identifiers starting with E and either a digit or an
> uppercase letter may be used for implementation-defined macros
> in <errno.h>, so a header name that happens to start with E might
> cause problems.  One way to avoid that is:
>
> #ifndef H_THING
> #define H_THING
> ...
> #endif /* H_THING */
>
> It's not terribly likely that an implementation is going to use
> _THING_H_ or EXTRA_FOO for its own purposes, so you can very likely
> get away with using such identifiers yourself, but if you avoid
> reserved identifiers you have one less thing to worry about.
>


--
Les Cargill

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what is the best way Andre <pas.mois@ailleur.be> - 2012-11-27 16:19 +0100
  Re: what is the best way Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-27 15:35 +0000
  Re: what is the best way Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-11-27 08:59 -0800
  Re: what is the best way James Kuyper <jameskuyper@verizon.net> - 2012-11-27 13:14 -0500
    Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-28 08:43 +1300
      Re: what is the best way James Kuyper <jameskuyper@verizon.net> - 2012-11-27 15:02 -0500
        Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-28 09:29 +1300
  Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 12:48 -0600
    Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-28 08:56 +1300
      Re: what is the best way Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-11-27 22:19 +0000
        Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 18:21 -0600
          Re: what is the best way Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-11-28 05:08 -0800
            Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-28 12:43 -0600
      Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 18:15 -0600
        Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-28 14:21 +1300
          Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 20:06 -0600
            Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-28 15:21 +1300
              Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 20:31 -0600
              Re: what is the best way glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-11-28 04:00 +0000
              Re: what is the best way Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-11-28 05:17 -0800
                Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-29 08:30 +1300
                Re: what is the best way Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-11-29 05:47 -0800
                Re: what is the best way Ian Collins <ian-news@hotmail.com> - 2012-11-30 07:37 +1300
                Re: what is the best way Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-11-29 11:35 -0800
    Re: what is the best way Keith Thompson <kst-u@mib.org> - 2012-11-27 17:25 -0800
      Re: what is the best way Les Cargill <lcargill99@comcast.com> - 2012-11-27 20:15 -0600
      Re: what is the best way pete <pfiland@mindspring.com> - 2012-11-27 23:48 -0500
    Re: what is the best way Sergio Durigan Junior <sergiodj@riseup.net> - 2012-11-28 03:06 -0200
      Re: what is the best way pete <pfiland@mindspring.com> - 2012-11-28 01:35 -0500
  Re: what is the best way pete <pfiland@mindspring.com> - 2012-11-28 00:13 -0500

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