docs: sysctl/kernel: document cad_pid

Based on the implementation in kernel/sysctl.c (the proc_do_cad_pid()
function), kernel/reboot.c, and include/linux/sched/signal.h.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200423183651.15365-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Stephen Kitt 2020-04-23 20:36:49 +02:00 committed by Jonathan Corbet
parent 2ad9a844fc
commit 6bc47621cb

View file

@ -116,6 +116,16 @@ run. The statistics can be seen using ``bpftool``.
= ===================================
cad_pid
=======
This is the pid which will be signalled on reboot (notably, by
Ctrl-Alt-Delete). Writing a value to this file which doesn't
correspond to a running process will result in ``-ESRCH``.
See also `ctrl-alt-del`_.
cap_last_cap
============