Linux service command
The service command starts or stops a service by running an initialization script.
service SCRIPT COMMAND [OPTIONS]
service --help | -h | --version
The SCRIPT parameter specifies an init script, located in /etc/init.d/SCRIPT, or the name of an upstart job in /etc/init. The existence of an upstart job of the same name as a script in /etc/init.d will cause the upstart job to take precedence over the init.d script. The supported values of COMMAND depend on the invoked script, service passes COMMAND and OPTIONS to the init script unmodified. For upstart jobs, start, stop, and status are passed through to their upstart equivalents. Restart will call the upstart 'stop' for the job, followed immediately by the 'start', and will exit with the return code of the start command. All scripts should support at least the start and stop commands. As a special case, if COMMAND is --full-restart, the script is run twice, first with the stop command, then with the start command. This option has no effect on upstart jobs.
"service --status-all" runs all init scripts, in alphabetical order, with the status command. This option only calls status for sysvinit jobs, upstart jobs can be queried in a similar manner with 'initctl list'.
init — The parent of all processes on the system.