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NAME

       start-stop-daemon - start and stop system daemon programs

SYNOPSIS

       start-stop-daemon [options] command

DESCRIPTION

       start-stop-daemon  is  used  to control the creation and termination of
       system-level  processes.   Using   one   of   the   matching   options,
       start-stop-daemon  can  be  configured  to find existing instances of a
       running process.

       Note: unless --pidfile is specified, start-stop-daemon behaves  similar
       to  killall(1).   start-stop-daemon will scan the process table looking
       for any processes which match the process name,  uid,  and/or  gid  (if
       specified). Any matching process will prevent --start from starting the
       daemon. All matching processes will be sent the TERM signal (or the one
       specified  via --signal or --retry) if --stop is specified. For daemons
       which have long-lived children which need to live through a --stop, you
       must specify a pidfile.

COMMANDS

       -S, --start [--] arguments
              Check  for  the  existence  of  a  specified process.  If such a
              process exists, start-stop-daemon does nothing, and  exits  with
              error  status 1 (0 if --oknodo is specified).  If such a process
              does  not  exist,  it  starts  an  instance,  using  either  the
              executable  specified  by --exec or, if specified, by --startas.
              Any arguments given after -- on  the  command  line  are  passed
              unmodified to the program being started.

       -K, --stop
              Checks  for  the  existence  of  a specified process.  If such a
              process exists, start-stop-daemon sends it the signal  specified
              by  --signal,  and exits with error status 0.  If such a process
              does not exist, start-stop-daemon exits with error status  1  (0
              if  --oknodo  is  specified).  If  --retry  is  specified,  then
              start-stop-daemon  will  check   that   the   process(es)   have
              terminated.

       -H, --help
              Show usage information and exit.

       -V, --version
              Show the program version and exit.

MATCHING OPTIONS

       -p, --pidfile pid-file
              Check whether a process has created the file pid-file.

       -x, --exec executable
              Check  for  processes  that  are  instances  of  this executable
              (according to /proc/pid/exe).

       -n, --name process-name
              Check for processes with the  name  process-name  (according  to
              /proc/pid/stat).

       -u, --user username|uid
              Check  for  processes owned by the user specified by username or
              uid.

OPTIONS

       -g, --group group|gid
              Change to group or gid when starting the process.

       -s, --signal signal
              With --stop, specifies the signal to  send  to  processes  being
              stopped (default TERM).

       -R, --retry timeout|schedule
              With  --stop,  specifies  that  start-stop-daemon  is  to  check
              whether the process(es) do  finish.  It  will  check  repeatedly
              whether  any  matching processes are running, until none are. If
              the processes do not exit it will then take  further  action  as
              determined by the schedule.

              If  timeout  is specified instead of schedule, then the schedule
              signal/timeout/KILL/timeout is used, where signal is the  signal
              specified with --signal.

              schedule  is  a  list of at least two items separated by slashes
              (/); each item may be -signal-number  or  [-]signal-name,  which
              means  to send that signal, or timeout, which means to wait that
              many seconds for processes to exit, or forever, which  means  to
              repeat the rest of the schedule forever if necessary.

              If  the  end  of  the  schedule  is  reached  and forever is not
              specified, then start-stop-daemon exits with error status 2.  If
              a schedule is specified, then any signal specified with --signal
              is ignored.

       -a, --startas pathname
              With --start, start the process specified by pathname.   If  not
              specified, defaults to the argument given to --exec.

       -t, --test
              Print  actions  that  would  be taken and set appropriate return
              value, but take no action.

       -o, --oknodo
              Return exit status 0 instead of 1 if no actions are  (would  be)
              taken.

       -q, --quiet
              Do   not   print  informational  messages;  only  display  error
              messages.

       -c, --chuid username|uid
              Change to this username/uid before starting the process. You can
              also  specify a group by appending a :, then the group or gid in
              the same way as you would for the `chown' command  (user:group).
              If a user is specified without a group, the primary GID for that
              user is used.  When using this option you must realize that  the
              primary  and  supplemental  groups  are set as well, even if the
              --group option is not specified. The --group option is only  for
              groups that the user isn't normally a member of (like adding per
              process group membership for generic users like nobody).

       -r, --chroot root
              Chdir and chroot to root before  starting  the  process.  Please
              note that the pidfile is also written after the chroot.

       -d, --chdir path
              Chdir  to  path  before starting the process. This is done after
              the chroot if the -r|--chroot option is set. When not specified,
              start-stop-daemon  will  chdir  to  the  root  directory  before
              starting the process.

       -b, --background
              Typically used with programs that don't  detach  on  their  own.
              This option will force start-stop-daemon to fork before starting
              the  process,  and  force  it  into  the  background.   WARNING:
              start-stop-daemon  cannot  check  the exit status if the process
              fails to execute for any reason. This is a last resort,  and  is
              only  meant  for  programs  that either make no sense forking on
              their own, or where it's not feasible to add the code  for  them
              to do this themselves.

       -N, --nicelevel int
              This alters the priority of the process before starting it.

       -P, --procsched policy:priority
              This  alters  the  process  scheduler policy and priority of the
              process before starting  it.  The  priority  can  be  optionally
              specified  by  appending  a : followed by the value. The default
              priority is 0. The currently supported policy values are  other,
              fifo and rr.

       -I, --iosched class:priority
              This  alters  the IO scheduler class and priority of the process
              before starting it. The priority can be optionally specified  by
              appending  a : followed by the value. The default priority is 4,
              unless class is idle,  then  priority  will  always  be  7.  The
              currently  supported  values for class are idle, best-effort and
              real-time.

       -k, --umask mask
              This sets the umask of the process before starting it.

       -m, --make-pidfile
              Used when starting a program that does not create  its  own  pid
              file.  This  option  will make start-stop-daemon create the file
              referenced with --pidfile and place the pid into it just  before
              executing  the  process. Note, the file will not be removed when
              stopping the program.  NOTE: This feature may not  work  in  all
              cases.  Most  notably when the program being executed forks from
              its main process. Because of this, it  is  usually  only  useful
              when combined with the --background option.

       -v, --verbose
              Print verbose informational messages.

EXIT STATUS

       start-stop-daemon  returns  0 if the requested action was performed, or
       if --oknodo is  specified  and  either  --start  was  specified  and  a
       matching process was already running, or --stop was specified and there
       were no matching processes. If --oknodo was not specified  and  nothing
       was  done, 1 is returned. If --stop and --retry were specified, but the
       end of the schedule was reached and the processes were  still  running,
       the error value is 2. For all other errors, the status is 3.

EXAMPLE

       Start  the  food daemon, unless one is already running (a process named
       food, running as user food, with pid in food.pid):

              start-stop-daemon --start --oknodo --user food --name food --pidfile /var/run/food.pid --startas /usr/sbin/food --chuid food -- --daemon

       Send SIGTERM to food and wait up to 5 seconds for it to stop:

              start-stop-daemon --stop --oknodo --user food --name food --pidfile /var/run/food.pid --retry 5

       Demonstration of a custom schedule for stopping food:

              start-stop-daemon --stop --oknodo --user food --name food --pidfile /var/run/food.pid --retry=TERM/30/KILL/5

AUTHORS

       Marek  Michalkiewicz  <marekm@i17linuxb.ists.pwr.wroc.pl>  based  on  a
       previous version by Ian Jackson <ian@chiark.greenend.org.uk>.

       Manual page by Klee Dienes <klee@mit.edu>, partially reformatted by Ian
       Jackson.