Reading binary data

Roel Schroeven rschroev_nospam_ml at
Wed Sep 10 21:06:39 CEST 2008

Aaron Scott schreef:
> Sorry, I had posted the wrong error. The error I am getting is:
>      struct.error: unpack requires a string argument of length 12
> which doesn't make sense to me, since I'm specifically asking for 11.

That's because of padding. According to the docs, "By default, C numbers 
are represented in the machine's native format and byte order, and 
properly aligned by skipping pad bytes if necessary (according to the 
rules used by the C compiler)". That means that struct.unpack() assumes 
one byte of padding between the 3-character string and the first 
unsigned int.

The saddest aspect of life right now is that science gathers knowledge
faster than society gathers wisdom.
   -- Isaac Asimov

Roel Schroeven

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