在 Debian/Ubuntu 系統上,有一個程式我們想要讓他在開機後自動執行,該怎麼做?
首先需要替要執行的程式撰寫一個啟動停止的 script 放在 /etc/init.d/ 目錄下,該 script 必須要可以接受參數 “start”、”stop” 等,來對應啟動或是停止。可以參考 /etc/init.d/skeleton 來做修改:
#! /bin/sh
### BEGIN INIT INFO
# Provides: skeleton
# Required-Start: $remote_fs $syslog
# Required-Stop: $remote_fs $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Example initscript
# Description: This file should be used to construct scripts to be
# placed in /etc/init.d.
### END INIT INFO
# Author: Foo Bar <foobar@baz.org>
#
# Please remove the "Author" lines above and replace them
# with your own name if you copy and modify this script.
# Do NOT "set -e"
# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="Description of the service"
NAME=daemonexecutablename
DAEMON=/usr/sbin/$NAME
DAEMON_ARGS="--options args"
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0
# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME
# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh
# Define LSB log_* functions.
# Depend on lsb-base (>= 3.2-14) to ensure that this file is present
# and status_of_proc is working.
. /lib/lsb/init-functions
#
# Function that starts the daemon/service
#
do_start()
{
# Return
# 0 if daemon has been started
# 1 if daemon was already running
# 2 if daemon could not be started
start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
|| return 1
start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
$DAEMON_ARGS \
|| return 2
# Add code here, if necessary, that waits for the process to be ready
# to handle requests from services started subsequently which depend
# on this one. As a last resort, sleep for some time.
}
#
# Function that stops the daemon/service
#
do_stop()
{
# Return
# 0 if daemon has been stopped
# 1 if daemon was already stopped
# 2 if daemon could not be stopped
# other if a failure occurred
start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
RETVAL="$?"
[ "$RETVAL" = 2 ] && return 2
# Wait for children to finish too if this is a daemon that forks
# and if the daemon is only ever run from this initscript.
# If the above conditions are not satisfied then add some other code
# that waits for the process to drop all resources that could be
# needed by services started subsequently. A last resort is to
# sleep for some time.
start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
[ "$?" = 2 ] && return 2
# Many daemons don't delete their pidfiles when they exit.
rm -f $PIDFILE
return "$RETVAL"
}
#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
#
# If the daemon can reload its configuration without
# restarting (for example, when it is sent a SIGHUP),
# then implement that here.
#
start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME
return 0
}
case "$1" in
start)
[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
do_start
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
stop)
[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
do_stop
case "$?" in
0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
esac
;;
status)
status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
;;
#reload|force-reload)
#
# If do_reload() is not implemented then leave this commented out
# and leave 'force-reload' as an alias for 'restart'.
#
#log_daemon_msg "Reloading $DESC" "$NAME"
#do_reload
#log_end_msg $?
#;;
restart|force-reload)
#
# If the "reload" option is implemented then remove the
# 'force-reload' alias
#
log_daemon_msg "Restarting $DESC" "$NAME"
do_stop
case "$?" in
0|1)
do_start
case "$?" in
0) log_end_msg 0 ;;
1) log_end_msg 1 ;; # Old process is still running
*) log_end_msg 1 ;; # Failed to start
esac
;;
*)
# Failed to stop
log_end_msg 1
;;
esac
;;
*)
#echo "Usage: $SCRIPTNAME {start|stop|restart|reload|force-reload}" >&2
echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
exit 3
;;
esac
:
或是如我們在嵌入式系統撰寫的簡易 script:
#! /bin/sh
# /etc/init.d/blah
#
# Some things that run always
touch /var/lock/blah
# Carry out specific functions when asked to by the system
case "$1" in
start)
echo "Starting script blah "
echo "Could do more here"
;;
stop)
echo "Stopping script blah"
echo "Could do more here"
;;
*)
echo "Usage: /etc/init.d/blah {start|stop}"
exit 1
;;
esac
exit 0
修改其權限為可執行
$ chmod 755 /etc/init.d/blah
使用 update-rc.d 更新開機 script
$ update-rc.d blah defaults
default 的意思是使用預設值,亦即在 runlevel 2 3 4 5 啟動(start), runlevel 0 1 6 停止 (stop)。若不想要使用預設值,也可以指定 runlevel 與執行的順序:
update-rc.d blah start 20 2 3 4 . start 30 5 . stop 80 0 1 6 .
上述指令的意思為在 runlevel 2 3 4 執行啟動順序為 20, runlevel 5 執行啟動順序為 30, runlevel 0 1 6 執行停止順序為 80Debian runlevel 定義:
0:關機 (Halt)
1:單一使用者模式 (single user mode)
2-5: 多使用者模式 (multi user mode)
6: 系統重啟 (reboot)
最後,若是要將其取消開機執行則使用以下命令
$ update-rc.d -f blah remove
延伸閱讀
請問這個daemon有辦法呼叫xinput或是gnome-control-center等應用程式嗎?