1024 file descriptors should be enough for anyone

[Robert Pluim]

But for those people who insist on using LSP with large codebases,
Emacs's use of 'select' is somewhat limiting.

Attached an initial attempt at using poll() instead of select(), and
bumping the open filed descriptor limit to 10240. It passes 'make
check' on GNU/Linux, FreeBSD 13, and macOS, and M-x eww
works. MS-Windows should still build with no change in functionality.

I haven't tried --with-pgtk or a lucid build, but I donʼt anticipate
any major issues there.

Comments welcome (I can stick it on a branch if needed). Things that
could be done:

- make the upper limit either statically or dynamically configurable
  (on GNU/Linux in theory you could have 1e6 open descriptors)
- a feature flag
- dynamic switching between poll and select

Thanks

Robert
--

0001-Allow-the-use-of-poll-instead-of-select.patch
Description: Text Data