[Python-Dev] runtime dlls on Windows

[Chris Barker]

On Thu, May 26, 2016 at 9:53 AM, Chris Angelico <rosuav at gmail.com> wrote:

> > BUT -- Steve Dower seems to have identified that the wonders of dll hell
> > never cease, and this isn't possible anyway. Oh well.
>
> I'm not entirely grasping what's happening here.


me neither :-(


> There are multiple
> versions of msvcp140.dll floating around out there; what happens if
> one app requires one of them and another requires another?


That's pretty much the dll hell that has plagued Windows FOREVER! why they
don't do some versioning is totally beyond me, though 8.3 filenames have
not been a restriction for a long time.


> Can you simply say "take the newer one"?


I *think* that standard Windows policy/practice is that newer versions of a
dll with the same name should always be backward compatible -- so something
built against an older version should work with the newer one -- so you can
ship a dll with a security patch, and it will all work. I presume that MS
itself is careful about this with their runtimes.


> Is there a way to instantly recognize
> that there's a newer one available, and ignore the older one?
>

I don't think so -- the linker will pick the first one it finds on the
search path :-(

-CHB


-- 

Christopher Barker, Ph.D.
Oceanographer

Emergency Response Division
NOAA/NOS/OR&R            (206) 526-6959   voice
7600 Sand Point Way NE   (206) 526-6329   fax
Seattle, WA  98115       (206) 526-6317   main reception

Chris.Barker at noaa.gov
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20160526/14e0f73a/attachment.html>