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Re: size_t in a struct

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Shao Miller wrote:

> On 5/20/2011 14:22, Edward Rutherford wrote:
>> Hello Group
>>
>>
> Hello. :)
> 
>> To avoid padding in structures, where is the best place to put size_t
>> variables?
>>
>> According the faq question 2.12 (http://c-faq.com/struct/padding.html),
>> it says:
>>
>> "If you're worried about wasted space, you can minimize the effects of
>> padding by ordering the members of a structure based on their base
>> types, from largest to smallest."
>>
>>
> And the sizes of those types can vary per implementation, too, if I
> recall correctly.
> 
>> So if I have the following:
>>
>> typedef struct __buffer_t {
>>
>>      char *buffer;
>>      size_t size;
>>
>> } Buffer_t;
>>
>> I should have mimized padding since size_t is an unsigned long.
> 
> It is?  How did you determine that?
> 
>> However, will size_t ever become an unsigned long long?
> 
> It might, as far as I know.

So standard-wise, how do I handle size_t in structures to minmize
padding?  Should size_t all ways follow after pointers in structures?
And if I have integers in the structure, where should I put size_t?

<OT>
According my style(9) man page, the suggestion is to:

"When declaring variables in structures, declare them sorted by use,
then
  by size (largest to smallest), then by alphabetical order. "

This would lead to padding, right?  But I would have to assume a size
for size_t to follow that style.
</OT>

Thanks.

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Thread

size_t in a struct Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-05-20 18:22 +0000
  Re: size_t in a struct Shao Miller <sha0.miller@gmail.com> - 2011-05-20 14:52 -0400
    Re: size_t in a struct Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-05-20 21:31 +0000
      Re: size_t in a struct Ian Collins <ian-news@hotmail.com> - 2011-05-21 09:51 +1200
        Re: size_t in a struct Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-24 21:34 +0300
          Re: size_t in a struct Ian Collins <ian-news@hotmail.com> - 2011-05-25 07:54 +1200
      Re: size_t in a struct "[the China Blue] Drill Baby Drill" <chine.bleu@yahoo.com> - 2011-05-20 15:06 -0700
        Re: size_t in a struct Angel <angel+news@spamcop.net> - 2011-05-20 22:51 +0000
      Re: size_t in a struct Keith Thompson <kst-u@mib.org> - 2011-05-20 15:39 -0700
        Re: size_t in a struct Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-05-21 18:00 +0000
          Re: size_t in a struct Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-05-21 14:12 -0600
          Re: size_t in a struct Keith Thompson <kst-u@mib.org> - 2011-05-21 16:31 -0700
            Re: size_t in a struct Dr Nick <3-nospam@temporary-address.org.uk> - 2011-05-22 10:08 +0100
              Re: size_t in a struct Shao Miller <sha0.miller@gmail.com> - 2011-05-22 13:24 -0500
                Re: size_t in a struct Ben Pfaff <blp@cs.stanford.edu> - 2011-05-22 10:37 -0700
                Re: size_t in a struct Uncle Steve <stevet810@gmail.com> - 2011-05-22 14:18 -0400
                Re: size_t in a struct Keith Thompson <kst-u@mib.org> - 2011-05-22 12:17 -0700
                Re: size_t in a struct David Thompson <dave.thompson2@verizon.net> - 2011-06-01 16:33 -0400
                Re: size_t in a struct Shao Miller <sha0.miller@gmail.com> - 2011-05-23 02:05 -0500
                Re: size_t in a struct Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-23 11:21 +0100
                Re: size_t in a struct Shao Miller <sha0.miller@gmail.com> - 2011-05-23 19:40 -0500
                Re: size_t in a struct Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-24 01:25 +0100
                Re: size_t in a struct Shao Miller <sha0.miller@gmail.com> - 2011-05-23 20:43 -0500
          Re: size_t in a struct gordonb.d6jvy@burditt.org (Gordon Burditt) - 2011-05-22 17:48 -0500
      Re: size_t in a struct Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-21 15:43 +0000
  Re: size_t in a struct Keith Thompson <kst-u@mib.org> - 2011-05-20 11:59 -0700
  Re: size_t in a struct Nobody <nobody@nowhere.com> - 2011-05-20 22:24 +0100

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