* PidRef conversion work:
- pid_is_unwaited() → pidref_is_unwaited()
- pid_is_alive() → pidref_is_alive()
- - unit_watch_pid() → unit_watch_pidref()
+ - is_kernel_thread() → pidref_is_kernel_thread()
+ - pid_is_my_child() → pidref_is_my_child()
+ - cg_pid_get_path() → cg_pidref_get_path()
+ - get_process_uid() → pidref_get_uid()
- actually wait for POLLIN on pidref's pidfd in service logic
- exec_spawn()
- serialization of control/main pid in service, socket, mount, swap units
- cg_pid_get_unit()
- openpt_allocate_in_namespace()
- scope dbus PIDs property needs to gain PIDFDs companion
+ - sd_bus_creds
+ - unit_attach_pid_to_cgroup_via_bus()
+ - cg_attach() – requires new kernel feature
+ - varlink_get_peer_pid()
* ddi must be listed as block device fstype