Yes, I get your meaning, and I totally agree with it, I was wondering what was the best way to do it, stay close to the cause, which would allow to more easily go along with changes, or put it in the configure file and warn the user as soon as possible... It was kind of a flip a coin decision in the end.

For my information, is there a kind of committee or someone taking these kinds of decisions or at least expressing rules as to the spirit in which they should be made?

On the same track, how can I find why someone wrote "
/* Various compilers have only certain posix functions */
/* XXX Gosh I wish these were all moved into pyconfig.h */
" in posixmodule.c? Is it just because no-one had the opportunity to do it and it is OK for me to do it?

"Fetchez la vache"