INVOKE-RC.D(8)		       Debian/GNU Linux 		INVOKE-RC.D(8)



NAME
       invoke-rc.d - executes System-V style init script actions

SYNOPSIS
       invoke-rc.d   [--quiet]	 [--force]   [--try-anyway]  [--disclose-deny]
       [--query] [--no-fallback] name action [init script parameters...]

       invoke-rc.d [--help]


DESCRIPTION
       invoke-rc.d is a generic interface  to  execute	System	V  style  init
       script  /etc/init.d/name  actions, obeying runlevel constraints as well
       as any local policies set by the system administrator.

       All access to the init scripts by Debian packages  maintainer  scripts
       should be done through invoke-rc.d.

       This manpage documents only the usage and behavior of invoke-rc.d.  For
       a discussion of the System V style init script arrangements please  see
       init(8)	and the dpkg Programmers Manual.  More information on invoke-
       rc.d can be found in the section on runlevels and init.d scripts of the
       Debian Policy Manual.


INIT SCRIPT ACTIONS
       The  standard  actions  are:  start, stop, force-stop, restart, reload,
       force-reload, and status.  Other actions are  accepted,	but  they  can
       cause  problems to policy-rc.d (see the INIT SCRIPT POLICY section), so
       warnings are generated if the policy layer is active.

       Please note that not all init scripts will implement  all  the  actions
       listed  above,  and  that  the  policy  layer may override an action to
       another action(s), or even deny it.

       Any extra parameters will be passed to the init	script(s)  being  exe
       cuted.

       If  an action must be carried out regardless of any local policies, use
       the --force switch.


OPTIONS
       --help Display usage help.

       --quiet
	      Quiet mode, no error messages are generated.

       --force
	      Tries to run the init  script  regardless  of  policy  and  init
	      script  subsystem  errors.   Use	of this option in Debian main
	      tainer scripts is severely discouraged.

       --try-anyway
	      Tries to run the init script if a non-fatal error is detected.

       --disclose-deny
	      Return status code 101 instead of status	code  0  if  the  init
	      script action is denied by the policy layer.

       --query
	      Returns  one  of the status codes 100-106. Does not run the init
	      script, and implies --disclose-deny and --no-fallback.

       --no-fallback
	      Ignores any fallback action requests by the policy layer.  Warn
	      ing:  this is usually a very bad idea for any actions other than
	      start.

STATUS CODES
       Should an init script be executed, invoke-rc.d always returns the  sta
       tus  code  returned  by the init script. Init scripts should not return
       status codes in the 100+ range (which is reserved in Debian and by  the
       LSB). The status codes returned by invoke-rc.d proper are:

       0      Success.	 Either the init script was run and returned exit sta
	      tus 0 (note that a fallback action may have been run instead  of
	      the one given in the command line), or it was not run because of
	      runlevel/local policy constrains and --disclose-deny is  not  in
	      effect.

       1 - 99 Reserved for init.d script, usually indicates a failure.

       100    Init  script  ID (name) unknown.	This means the init script was
	      not registered successfully through update-rc.d or that the init
	      script does not exist.

       101    Action  not allowed.  The requested action will not be performed
	      because of runlevel or local policy constraints.

       102    Subsystem error.	Init script (or policy layer)  subsystem  mal
	      function. Also, forced init script execution due to --try-anyway
	      or --force failed.

       103    Syntax error.

       104    Action allowed.  Init script would be run,  but  --query	is  in
	      effect.

       105    Behavior uncertain.  It cannot be determined if action should be
	      carried out or not, and --query is in effect.

       106    Fallback	action	requested.   The  policy  layer   denied   the
	      requested  action, and supplied an allowed fallback action to be
	      used instead.


INIT SCRIPT POLICY
       invoke-rc.d introduces the concept of a policy layer which is  used  to
       verify  if  an  init  script should be run or not, or if something else
       should be done instead.	This layer has various uses, the most  immedi
       ate ones being avoiding that package upgrades start daemons out-of-run
       level, and that a package starts or stops daemons while inside a chroot
       jail.

       The  policy layer has the following abilities: deny or approve the exe
       cution of an action; request that another action (called a fallback) is
       to  be  taken, instead of the action requested in invoke-rc.ds command
       line; or request multiple actions to be tried in order,	until  one  of
       them succeeds (a multiple fallback).

       invoke-rc.d itself only pays attention to the current runlevel; it will
       block any attempts to start a service in a runlevel in which  the  ser
       vice  is  disabled.  Other policies are implemented with the use of the
       policy-rc.d helper, and are only available if /usr/sbin/policy-rc.d  is
       installed in the system.


FILES
       /etc/init.d/*
	      System V init scripts.

       /usr/sbin/policy-rc.d
	      Init script policy layer helper (not required).

       /etc/runlevel.conf
	      file-rc  runlevel configuration (if the file-rc package is being
	      used).

       /etc/rc?.d/*
	      System V runlevel configuration (if the sysv-rc package  is  not
	      being used).


BUGS
       Please	report	 any  bugs  using  the	Debian	bug  tracking  system,
       http://bugs.debian.org/, packages  sysv-rc  or  file-rc	(depending  on
       which version of invoke-rc.d you are using).

SEE ALSO
       dpkg Programmers manual,
       /etc/init.d/skeleton,
       update-rc.d(8),
       init(8),
       /usr/share/doc/sysv-rc/README.policy-rc.d



Debian Project			 1 March 2001			INVOKE-RC.D(8)