From 9e33f349d489f24da7e1c93e85d826df8ad9ae5b Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 25 Mar 2014 00:51:22 +0100 Subject: [PATCH] systemctl: add more verbose explanation of --kill-who and what control/main processes are (cherry picked from commit af7424af70d063412c09b0125f4d4a39865210dc) (cherry picked from commit e28c1308c99a4172d99304d927d675e29d0b7fa5) --- man/systemctl.xml | 35 ++++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) diff --git a/man/systemctl.xml b/man/systemctl.xml index 816586c39e..6492b0ef96 100644 --- a/man/systemctl.xml +++ b/man/systemctl.xml @@ -389,11 +389,36 @@ systemctl start foo When used with kill, choose which - processes to kill. Must be one of , - or to select - whether to kill only the main process of the unit, the - control process or all processes of the unit. If omitted, - defaults to . + processes to send a signal to. Must be one of + , or + to select whether to kill only the main + process, the control process or all processes of the + unit. The main process of the unit is the one that defines + the life-time of it. A control process of a unit is one that + is invoked by the manager to induce state changes of it. For + example, all processes started due to the + ExecStartPre=, + ExecStop= or + ExecReload= settings of service units are + control processes. Note that there is only one control + process per unit at a time, as only one state change is + executed at a time. For services of type + Type=forking the initial process started + by the manager for ExecStart= is a + control process, while the process ultimately forked off by + that one is then considered the main process of the unit (if + it can be determined). This is different for service units + of other types, where the process forked off by the manager + for ExecStart= is always the main process + itself. A service unit consists of no or one main process, + no or one control process plus any number of additional + processes. Not all unit types manage processes of these + types however. For example for mount units control processes + are defined (which are the invocations of + /usr/bin/mount and + /usr/bin/umount), but no main process + is defined. If omitted, defaults to + .