The `ProcessManager` is a singleton class to handle `SIGCHLD` signals and report the exit status to the particular `Process` instance. However, having a singleton in a library is not favourable and it is even less favourable if it installs a signal handler. Using pidfd it is possible to avoid the need for the signal handler; and the `Process` objects can watch their pidfd themselves, eliminating the need for the `ProcessManager` class altogether. `P_PIDFD` for `waitid()` was introduced in Linux 5.4, so this change raises the minimum supported kernel version. `clone3()`, `CLONE_PIDFD`, `pidfd_send_signal()` were all introduced earlier. Furthermore, the call to the `unshare()` system call can be removed as those options can be passed to `clone3()` directly. Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
948 B
948 B