[Python-Dev] RE: NT select.select?

Brian Lloyd Brian@digicool.com
Fri, 30 Jul 1999 10:23:49 -0400

> Is there some low limit on maximum number of sockets you can 
> have in the
> Python-NT's select call? A program that happens to work 
> perfectly on Linux
> seems to die on NT around 64(?) sockets to the 'too many file 
> descriptors
> in call' error.
> Any portable ways to bypass it?
> -Markus

Hi Markus,

It turns out that NT has a default 64 fd limit on arguments to
select(). The good news is that you can actually bump the limit up 
to whatever number you want by specifying a define when compiling 

If you have the ability to rebuild your python15.dll, you can add
the define:


to the preprocessor options for the python15 project to raise the
limit to 1024 fds.

The default 64 fd limit is too low for anyone trying to run
an async server that handles even a modest load, so I've 
submitted a bug report to python.org asking that the define
above find its way into the next python release...

Brian Lloyd        brian@digicool.com
Software Engineer  540.371.6909              
Digital Creations  http://www.digicool.com