[Python-Dev] Inherance of file descriptor and handles on Windows (PEP 446)

[Antoine Pitrou]

On Wed, 24 Jul 2013 10:56:05 -0700
Guido van Rossum <guido at python.org> wrote:
> 
> But I'm also ready to propose that all this is such a mess that we
> *should* change the default fd/handle inheritance to False, *across
> platforms*, and damn the torpedoes -- i.e. accept breaking all
> existing 3rd party UNIX code for subprocess creation that bypasses the
> subprocess module, as well as breaking uses of os.spawn*() on both
> platforms that depend on FD inheritance beyond stdin/stdout/stderr).

So I suppose you mean "change it to False except for
stdin/stdout/stderr"?

> With the new, sane default, all we need instead of PEP 446 is a way to
> make an FD inheritable after it's been created, which can be a single
> os.make_inheritable(fd) call that you must apply to the fileno() of
> the stream or socket object you want inherited (or directly to a FD
> you created otherwise, e.g. with os.pipe()). On Windows, this should
> probably only work with os.spawn*(), since otherwise you need *handle*
> inheritance, not *FD* inheritance, and that's a non-portable concept
> anyway.

I'm not sure how *fd* inheritance could work without *handle*
inheritance.
(since a fd seems to just be a proxy for a handle)

> To reduce the need for 3rd party subprocess creation code, we should
> have better daemon creation code in the stdlib -- I wrote some damn
> robust code for this purpose in my previous job, but it never saw the
> light of day.

What do you call "daemon"? An actual Unix-like daemon?

Regards

Antoine.