On Thu, May 28, 2026 at 05:52:21PM +0800, Li Chen wrote:

Hi,

This is an early RFC for an idea that is probably still rough in both the
UAPI and implementation details. Sorry for the rough edges; I am sending
it now to check whether this direction is worth pursuing and to get
feedback on the kernel/userspace boundary.

The idea of having a builder api for exec isn't all that crazy. But it
should simply be built on top of pidfds and thus pidfs itself instead.
It has all the basic infrastructure in place already. Any implementation
should also allow userspace to implement posix_spawn() on top of it.

fd = pidfd_open(0, PIDFD_EMPTY /* or better name */)

pidfd_config(fd, ...) // modeled similar to fsconfig()