[erlang-questions] Passing data between Erlang and C port while preserving padding and alignment?

[Frank Muller]

Hi guys

Let assume the following C structure (I have a bunch of them, all
different):

struct foo {
 int32 i32;
 char c;
 int64 i64;
 char * p;
 float f;
 char * str[16];
};

When it gets compiled, GCC will add some padding to align data types (i.e
self-alignment). More info at:

http://www.catb.org/esr/structure-packing/

On the Erlang side, it is very easy to generate a binary which matches this
C structure field by field.
But it won’t work because of the padding :-/

Question: how can I derive the GCC's padding, and automatically add it to
my Erlang binary?

I am open to any generic/flexible solutions even if I have to auto-generate
these C structures (i.e meta-programming).

Thank you.
/Frank
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