On 05/17, Aleksa Sarai wrote: > > On 2019-05-16, Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > On 05/16, Christian Brauner wrote: > > > > > > With the introduction of pidfds through CLONE_PIDFD it is possible to > > > created pidfds at process creation time. > > > > Now I am wondering why do we need CLONE_PIDFD, you can just do > > > > pid = fork(); > > pidfd_open(pid); > > While the race window would be exceptionally short, there is the > possibility that the child will die Yes, > and their pid will be recycled > before you do pidfd_open(). No. Unless the caller's sub-thread does wait() before pidfd_open(), of course. Or unless you do signal(SIGCHILD, SIG_IGN). Oleg.
