Date: Wed, 19 Mar 2003 06:25:44 +0200
From: "Eli Zaretskii" <eliz AT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: djgpp AT delorie DOT com
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In-reply-to: <20030318223107.25581.00000232@mb-dh.aol.com> (dang2015@aol.com)
Subject: Re: "pragma pack" question
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> From: dang2015 AT aol DOT com (DanG2015)
> Newsgroups: comp.os.msdos.djgpp
> Date: 19 Mar 2003 03:31:07 GMT
> 
> As a side note, I read a post where someone said something such
> as "padding hurts portability".  I think this is just the opposite;  If you
> can control the size of structs, especially with binary I/O ACROSS
> multiple platforms, you enhance portability

Binary I/O of struct's is never portable.  If you want to write a
portable program that uses binary I/O, you need to manually insert
bytes from the struct into an array declared `unsigned char', and
swap the bytes to the ``network order'' befopre doing that with
functions `htonl' and `htons'.

> As I said, the output surprised me:
> 
> sizeof A = 2
> sizeof B = 2
> sizeof C = 2
> sizeof D = 2

This is expected: `char' entities don't need any alignment, so the
output is unaffected.