Subj : Re: Win98 error
To   : borland.public.cpp.borlandcpp
From : maeder@glue.ch (Thomas Maeder [TeamB])
Date : Tue Mar 16 2004 08:18 pm

Bob Gonder <notbg@notmindspring.invalid> writes:

>>ints in structs don't cause them to break on different platforms. Why do you
>>think they do?
>
> They're different sizes, no?

In general, yes.


> Write a struct on one platform, read it on another, and not-so-good
> things happen.

Not-so-good things only happen if a struct's binary representation is written
on one platform and is attempted to be read on a different platform.

Independently of there being an int member. With floating members, chances
that you get problems, are much higher.

This problem is known, and so is the solution: the definition of a protocol
that exactly specifies the meaning of every byte transfered. The easiest
realization is some textual representation, e.g. XML or something less
verbose.


> If you can use fixed-size values short, long, int64, of what use is a
> variable sized int in a struct?

First, short and long objects aren't of fixed size. Second, size is only
one of the issues to be taken into consideration. Endianness is another.

.