[Python-Dev] FW: [Python-Help] Python threads with suncc (Forte 6.1) compiler

Guido van Rossum guido@zope.com
Sat, 04 Aug 2001 02:29:08 -0400

> Some Socket Wizard should worry about the attached.  What's life like on
> 64-bit Linux (etc)?

Dunno, but I doubt 64-bit Linux would be so dumb as to declare
FD_SETSIZE to be 2**16.

> Perhaps more autoconf crap could fudge this.

I think we can avoid this.

> once-again-windows-shows-the-way<wink>-ly y'rs  - tim

Yes, in a very simple way: instead of testing for MS_WINDOWS, we could
test for a preposterous value of FD_SETSIZE.  For example, change all
three occurrences of

    #ifdef MS_WINDOWS


    #if FD_SETSIZE > 1024

Looking at the code, a better solution may be to always allocate this
thing on the heap, and to let list2set allocate it.  The actual number
of items *used* is the length of the list of file descriptors + 1 (a
sentinel).  Even if FD_SETSIZE is not preposterous, the array size
allocated is the theoretical maximum, which is always ways larger than
the size needed.  (I also fail to understand why 3 extra elements are
allocated; the algorithm seems to need only one extra.)

Yet another approach would (shrudder :) be to forget about arrays and
use a Python dict, since that's the usage: the data structure stores
the mapping between file descriptors (unique small ints) and objects
in the argument lists (either Python ints or objects with a fileno()

Volunteers?  Not me! :)

--Guido van Rossum (home page: http://www.python.org/~guido/)