On May 26, 2014, at 4:20 PM, Graham Cox <graham....@bigpond.com> wrote:

> That's just as wrong - you are using the first few bytes of the data as the 
> length, which it certainly isn't (except for possibly a very few special 
> cases that just so happen to have the length as the first field of the data).

No, it’s extremely common to have a data format where a variable-length field 
is prefixed with its length. That looks like what this code is trying to read.

The right way to do this would be something like:
        uint32_t length = *(uint32_t*)bytes;
        length = CFSwapInt32BigToHost(length);
You need to be explicit about the size of integer in use (“int” has different 
sizes on different platforms) and you need to convert from the byte-order used 
in the file format (which is almost always big-endian.)

—Jens
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