Ubuntu Manpage: invoke-run - runscript interpreter

Provided by: runit_2.1.2-44ubuntu2_amd64

NAME

       invoke-run - runscript interpreter

SYNOPSIS

       /usr/bin/env /lib/run/invoke-run

DESCRIPTION

The runit supervision system uses scripts, called runscripts to start services. By
convention, runscript for a service foo is located at /etc/sv/foo/run

Debhelper addon dh_runit installs runscript according this convention.

Runscript can be any executable file. Runscript can use invoke-run interpreter only if it
is installed according convention,

To use invoke-run interpreter, runscript /etc/sv/foo/run for service foo must begin with
following line:

#!/usr/bin/env /lib/runit/invoke-run

If the script /usr/sbin/policy-rc.d exists the policy layer is checked (see below). If
init.d script /etc/init.d/foo exists, it is invoked with stop argument to gracefully
handle package upgrade to version, introducing runscript. After that, /bin/sh shell
interpret rest of runscript, with some additional environment set according following
rules:

A NAME=foo variable is exported.

The /etc/default/runit file is interpreted with /bin/sh and all variable assignment
are accessible to runscript.

If file /etc/default/foo exists, it is interpreted with /bin/sh and all variable
assignment are accessible to runscript.

If directory /etc/sv/foo/conf exists, variables are set according to rules, documented
in envdir section of chpst(8) manual.

If both /etc/default/foo file and /etc/sv/foo/conf directory define some variable, value
from directory takes precedence.

SPECIAL ERROR CODE

       Looking in the foo service log it's possible to see messages in the form of

         invoke-run: ERROR [NNN] in foo: reason for the error

       These messages don't come from runsv itself but from  invoke-run,  the  run  file  or  the
       finish  file. The purpose of these message is to detail a permanent failure condition that
       prevents foo service from being up.  For each foo service, possible  errors  and  messages
       are:

         invoke-run: foo binary not installed

           this happens when the package containing foo binary has been removed, but not purged.

         invoke-run: ERROR -1 in foo: runscript didn't exit normally

           this  message comes from the finish file, but the exit code comes from runsv(8) and is
           documented in its manpage.

         invoke-run: WARNING for foo: disabled by local settings

           Some service specific setting prevent foo from  starting;  it's  likely  something  in
           /etc/default/foo

         invoke-run: ERROR 162 in foo: configtest or early setup failed

           A  configuration  file  of  foo  is  malformed  and the configtest failed; foo log may
           contain additional info from the test itself.  Alternatively the runscript has  failed
           to do some setup that is essential to the foo service.

         invoke-run: ERROR 170 in foo: a runtime hard dependency is missing

           A  dependency  failed  the  check  and  can't be bring up; to know dependencies of foo
           service look for "sv start" in "run" script.

FINISH FILE AND FINISH-DEFAULT

       Since version 2.1.2-36 the Debian runit package  ships  a  /lib/runit/finish-default  file
       that contains code that can be shared across different services.  This file can be sourced
       inside the regular finish file of a service, like the following example

        $ cat /etc/sv/foo/finish
        #!/bin/sh
        set -e
        . /lib/runit/finish-default "$@"

       Services that need to put specific code into the finish file should do after the line that
       sources    finish-default.   For   each   foo   service,   finish-default   file   sources
       /etc/default/runit, export  a  NAME=foo  variable  and  defines  special  error  codes  as
       described in the previous section.  Also, when VERBOSE mode is on, EXIT is trapped so that
       a 'foo stopped' message gets printed at the very end of the finish file.

POLICY-RC.D LAYER