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runsv(8)


NAME

   runsv  -  starts and monitors a service and optionally an appendant log
   service

SYNOPSIS

   runsv service

DESCRIPTION

   service must be a directory.

   runsv switches to the directory service and  starts  ./run.   If  ./run
   exits  and ./finish exists, runsv starts ./finish.  If ./finish doesn't
   exist or ./finish exits, runsv restarts ./run.

   If ./run or ./finish exit immediately,  runsv  waits  a  second  before
   starting ./finish or restarting ./run.

   Two  arguments  are  given  to ./finish.  The first one is ./run's exit
   code, or -1 if ./run didn't exit normally.  The second one is the least
   significant  byte  of  the exit status as determined by waitpid(2); for
   instance it is 0 if ./run exited normally, and  the  signal  number  if
   ./run was terminated by a signal.  If runsv cannot start ./run for some
   reason, the exit code is 111 and the status is 0.

   If  the  file  service/down  exists,  runsv  does   not   start   ./run
   immediately.   The  control  interface (see below) can be used to start
   the service and to give other commands to runsv.

   If the directory service/log exists, runsv creates  a  pipe,  redirects
   service/run's   and  service/finish's  standard  output  to  the  pipe,
   switches to the directory service/log  and  starts  ./run  script.  The
   standard input of the log service is redirected to read from the pipe.

   runsv  maintains  status  information in a binary format (compatible to
   the daemontools' supervise  program)  in  service/supervise/status  and
   service/log/supervise/status,   and   in  a  human-readable  format  in
   service/supervise/stat,                     service/log/supervise/stat,
   service/supervise/pid, service/log/supervise/pid.

CONTROL

   The    named    pipes   service/supervise/control,   and   (optionally)
   service/log/supervise/control are provided to give commands  to  runsv.
   You  can  use  sv(8)  to  control  the service or just write one of the
   following characters to the named pipe:

   u      Up.  If the service is not running, start it.   If  the  service
          stops, restart it.

   d      Down.   If  the  service  is running, send it a TERM signal, and
          then a CONT signal.   If  ./run  exits,  start  ./finish  if  it
          exists.  After it stops, do not restart service.

   o      Once.   If the service is not running, start it.  Do not restart
          it if it stops.

   p      Pause.  If the service is running, send it a STOP signal.

   c      Continue.  If the service is running, send it a CONT signal.

   h      Hangup.  If the service is running, send it a HUP signal.

   a      Alarm.  If the service is running, send it a ALRM signal.

   i      Interrupt.  If the service is running, send it a INT signal.

   q      Quit.  If the service is running, send it a QUIT signal.

   1      User-defined 1.  If the service  is  running,  send  it  a  USR1
          signal.

   2      User-defined  2.   If  the  service  is  running, send it a USR2
          signal.

   t      Terminate.  If the service is running, send it a TERM signal.

   k      Kill.  If the service is running, send it a KILL signal.

   x      Exit.  If the service is running, send it  a  TERM  signal,  and
          then a CONT signal.  Do not restart the service.  If the service
          is down, and no log service exists, runsv exits.  If the service
          is  down  and  a  log  service exists, runsv closes the standard
          input of the log service, and waits for it to terminate.  If the
          log service is down, runsv exits.  This command is ignored if it
          is given to service/log/supervise/control.

   Example: to send a TERM signal to the socklog-unix service, either do
     # sv term /etc/service/socklog-unix
    or
     # printf t >/etc/service/socklog-unix/supervise/control

   printf(1) usually blocks if no runsv process is running in the  service
   directory.

CUSTOMIZE CONTROL

   For  each  control  character  c  sent to the control pipe, runsv first
   checks if service/control/c exists and is executable.  If so, it starts
   service/control/c  and  waits  for it to terminate, before interpreting
   the command.  If the program exits with return code 0,  runsv  refrains
   from  sending  the  service the corresponding signal.  The command o is
   always considered as command u.  On command d  first  service/control/t
   is   checked,   and   then   service/control/d.   On  command  x  first
   service/control/t is checked, and then service/control/x.  The  control
   of the optional log service cannot be customized.

SIGNALS

   If  runsv  receives  a  TERM  signal, it acts as if the character x was
   written to the control pipe.

EXIT CODES

   runsv exits 111 on an error on startup or if another runsv  is  running
   in service.

   runsv exits 0 if it was told to exit.

SEE ALSO

   sv(8),   chpst(8),  svlogd(8),  runit(8),  runit-init(8),  runsvdir(8),
   runsvchdir(8), utmpset(8)

   http://smarden.org/runit/

AUTHOR

   Gerrit Pape <pape@smarden.org>

                                                                  runsv(8)



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