[Python-Dev] Changing ob_size to [s]size_t

M.-A. Lemburg mal@lemburg.com
Thu, 06 Jun 2002 12:19:17 +0200

Martin v. L=F6wis wrote:
> What terrible things would happen if ob_size would be changed from int
> to size_t?

This would cause binary incompatibility for all extension
types on 64-bit systems since the object struct layout
would change (probably not much of an issue since
binary compatiblity is not guaranteed between releases anyway).

> The question recently came up on comp.lang.python, where the poster
> noticed that you cannot mmap large files on a 64-bit system where int
> is 32 bits; there is a 2Gib limit on the length of objects on his
> specific system.

Wouldn't it be easier to solve this particular problem in
the type used for mmapping files ?

> About the only problem I can see is that you could not store negative
> numbers anymore. Is ssize_t universally available, or could be used on
> systems where it is available?

Marc-Andre Lemburg
CEO eGenix.com Software GmbH
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