runsv(8)                                                      System Manager's Manual                                                     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  ser-
       vice 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 (and ./finish) exactly as described above for the service directory.   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)