Re: Structure size and binary format

gamehack wrote: 

I've been wondering when I write a structure like:

struct {
  int          a;
  unsigned int b;
  float        c;
} mystruct;

And then I'm using this as a record for a binary file. The
problem is that the size of the types is different on different platforms(win/lin/osx) so if a file was copied on another
platform and attempted to be read then the first say 16 bytes
could be regarded as the integer a but it could have been
created on system where integer was 32 bytes.

Good. You recognize the existence of a problem. The answer is "Don't do that". Binary representations are, in general, not portable. You can convert things into a sequence of bytes and write/read those to a file, but that means you also have to write the conversion mechanisms. Now such things as byte sex can bite you.

Far and away the most portable transportation mechanism is pure text. You already have conversion routines in the standard library, and all you need to do is use them. Anybody and their dog can read the files.

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