From:	Thomas Demmer <demmer AT LSTM DOT Ruhr-UNI-Bochum DOT De>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: The size of structures and binary files
Date:	Fri, 13 Jun 1997 15:53:28 +0100
Organization:	Lehrstuhl fuer Stroemungsmechanik
Lines:	37
Message-ID:	<33A15EE8.794B@LSTM.Ruhr-UNI-Bochum.De>
References:	<33A1B030 DOT 309E AT post DOT psychologie DOT uni-bielefeld DOT de>
NNTP-Posting-Host:	bvb.lstm.ruhr-uni-bochum.de
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

News Administrator wrote:
> 
> Dear DJGPP users!
> 
> Recently I came across something weird:
> I have two structs:
> struct s1 { char c1; char c2; short s};
> struct s2 { char c1; short s; char c2};
> 
> A call to sizeof will return 4 for s1 and 6 (!) for s2.
> It seems like the size of the chars in s2 gets increased to 2.
> 
[...]

Welcome to the world of alignment.
Just say

#pragma pack(1)
struct s1 { char c1; char c2; short s};
struct s2 { char c1; short s; char c2};
#pragma pack()


-- 
Ciao
Tom

*************************************************************
* Thomas Demmer                                             *
* Lehrstuhl fuer Stroemungsmechanik                         *
* Ruhr-Uni-Bochum                                           *
* Universitaetsstr. 150                                     *
* D-44780  Bochum                                           *
* Tel: +49 234 700 6434                                     *
* Fax: +49 234 709 4162                                     *
* http://www.lstm.ruhr-uni-bochum.de/~demmer                *
*************************************************************

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