Victor Stinner firstname.lastname@example.org writes:
Q: The PEP may break applications. A: Most developers agree that it is (very) unlikely. If file descriptor inherance matters, subprocess must be used (because it rocks!) with pass_fds.
But that doesn't cover the case for programs that don't fork and really just want to exec another program. when using subprocess, you'll always have two processes running.
If subprocess is used without pass_fds, applications stops working since python 3.2 (since python 3.0 on Windows). pass_fds will clear the close-on-exec flag on the file descriptors with the PEP. If an application breaks because it relies on file descriptor inherance, it's easy to detect it (EBADF error) and
the application may open other files/sockets and the unused file descriptor would be reused. there's no EBADF in that case.