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Re: I need help

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On 05/16/11 02:45 PM, pete wrote:
> 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.

Well OK, I was thinking an extern pointer declaration, but that would be 
a messy mix.

-- 
Ian Collins

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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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