Beam file format questions.

Bjorn Gustavsson <>
Tue Aug 27 08:49:51 CEST 2002


You might find it easier to use the beam_lib module in stdlib
instead of writing your own code.

/Bjorn

Eric Merritt <> writes:

> 
> First, the 'Atom' and 'Code' chunks seem to have an
> extra two null bytes padded onto the end of thier
> chunks (beyond the length specified in the chunk
> header). The other chunks seem to obey the format
> specified in the above document. It could very well be
> that I am just a bit off in the head and missing
> something. Hopefully, one of you will confirm. 

Chunks are aligned to a four-byte boundary. I think
that is mentioned in the specification.

> 
> Second, the 'ExpT' chunks doesn't seem too useful to
> me at all. I am exporting two functions in my test
> code, so accoring to the spec there  should be a total
> of 24 bytes (12 bytes per exported function '3*4') of
> information after the chunk header, in mine there are
> 52 bytes. I hope one of you with a little more insight
> and experience can explain where I am screwing up.
> Following is some code I am using to generate the beam
> file I am testing with, it doesn't do anything at all
> really except produce a beam file.

The compiler always generates two extra functions in
each module: module_info/0,1.

-- 
Björn Gustavsson            Ericsson Utvecklings AB
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