Upgrading Python Breaks Extensions; Fix proposal

[Alex Martelli]

"Neil Schemenauer" <nas at python.ca> wrote in message
news:mailman.999095450.14153.python-list at python.org...
> Skip Montanaro wrote:
> >
> >     John> Under Unix, each program is its own address space, and .so
modules
> >     John> are private resources once they're loaded.
> >
> > I might be reading this wrong, and I'm definitely taking you out of
context,
> > but the whole idea of .so files is that their text sections *are* shared
> > among processes.  Their data sections will be process-private.
>
> That's an optimization done at the OS level however.  The process does
> not see it.  I think (perhaps incorrectly) that John is saying that the
> sharing is done in a less transparent fashion on Windows.  Can someone
> confirm?

No, I cannot confirm this -- the read-only code segments are
transparently shared in Windows, too.  Maybe John's point was
that a Windows DLL *CAN* declare it has shared-data -- few do
so nowadays, since a cleaner way for shared-memory for IPC
is provided by memory-mapping, but I'm pretty sure it's still
possible (the flags for that are provided in the "Intel
Portable Executable" format on which Microsoft's .EXE and
.DLL fileformats are based).


> I don't know how this relates to the original question however.

Me neither, actually.  But it's the kind of useless trivia
that's so much fun to debate!-)


Alex