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Re: I need help

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Ian Collins wrote:
> 
> On 05/15/11 06:29 AM, Heinrich Wolf wrote:
> >
> > or with a macro:
> >
> > #define STRNCAT(a, b) strncat(a, b, sizeof(a) - strlen(a) - 1)
> > char string[10] = "NEW";
> > STRNCAT(string, "Jersey");
> 
> That macro would go horribly (and silently) wrong if
> 
> a) 'a' wasn't a fixed sized array, or
> b) it was, but the definition wasn't visible
>    when the macro was expanded.

If (a) was a fixed sized array, 
but the definition wasn't visible when the macro was expanded,
then (a) would be an incomplete type
and (sizeof a) would cause the generation of a diagnostic message,
rather than go silently wrong.

-- 
pete

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Re: I need help janus <emekamicro@gmail.com> - 2011-05-14 11:15 -0700
  Re: I need help "Heinrich Wolf" <invalid@invalid.invalid> - 2011-05-14 20:29 +0200
    Re: I need help Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-15 13:03 +0300
      Re: I need help "Heinrich Wolf" <invalid@invalid.invalid> - 2011-05-15 13:18 +0200
        Re: I need help Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-16 04:31 +0300
    Re: I need help Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-15 08:13 -0400
      Re: I need help "Heinrich Wolf" <invalid@invalid.invalid> - 2011-05-15 14:30 +0200
        Re: I need help Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-15 08:45 -0400
          Re: I need help Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-16 04:34 +0300
    Re: I need help Ian Collins <ian-news@hotmail.com> - 2011-05-16 13:42 +1200
      Re: I need help Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-16 03:28 +0100
      Re: I need help pete <pfiland@mindspring.com> - 2011-05-15 22:45 -0400
        Re: I need help Ian Collins <ian-news@hotmail.com> - 2011-05-16 14:50 +1200
      Re: I need help "Heinrich Wolf" <invalid@invalid.invalid> - 2011-05-16 12:26 +0200
  Re: I need help Keith Thompson <kst-u@mib.org> - 2011-05-14 11:33 -0700
  Re: I need help Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-15 07:58 -0400

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