`configure` option for epoll disable

[mtelka]

The illumos implementation of epoll is not good enough to be used by Python and so OpenIndiana modifies the configure script to make sure the epoll is not detected (and so not used). Here are patches for Python 3.7, 3.9, 3.12, and 3.13.

It would be great if there is some configure option to disable epoll so we do not need to cary these patches.

Thank you.

Linked PRs

• gh-138850: Add --disable-epoll to configure #145768

[encukou]

Under the unsupported platforms policy, I think a PR adding a --without-epoll option would be acceptable. Do you want to write one?

If you can modify pyconfig.h after configuring, consider sedding out #define HAVE_EPOLL 1 out, or undefining it at the end. That might need fewer adjustments between the releases.

[encukou]

I'll close for now; let's reopen if you want to work on a configure patch.

[vstinner]

Here are patches for Python 3.7, 3.9, 3.12, and 3.13.

Copy of the Python 3.13 patch description:

Without this patch, python detects and uses epoll which only exists in
OmniOS for lx zones and Linux compatibility. It is not quite the same as
the Linux implementation and can cause socket related failures in python.

There is no nice way to tell configure that we don't have it
(pkgsrc get around this by installing a broken epoll.h into the build
chroot area).