INITCTL(8)

NAME
initctl - utility to control simpleinit(8)

SYNOPSIS
need [-r] service
display-services
provide service

OVERVIEW
The initctl programme is designed to help improve the robustness, scalability and readability of system boot scripts. It is now possible to write a modularised set of boot scripts without the complex and fragile numbered symlink scheme used in SysV-style boot scripts. Each script can simply declare, using need(8), what must run before them.

DESCRIPTION for need
The need programme is a utility that tells simpleinit(8) to start a service (usually a script in /sbin/init.d) and will wait for the service to become available. If the service is already available, it will not be started again.

The -r option is used to tell simpleinit(8) to "roll back" (stop) services up to (but not including) service. If service is not specified, all services are stopped. The -r option thus allows the system to be partially or wholly shut down in an orderly fashion. The shutdown(8) programme still needs to be run.

DESCRIPTION for display-services
When invoked as display-services it will write the list of currently available services and the list of failed services to the standard output.

DESCRIPTION for provide
When invoked as provide it tells simpleinit(8) that the parent (calling) process will be providing a service with name service. If the calling process exits successfully (status 0) the service is deemed to be available. Only one instance of service may be started, so alternate providers will block and may fail.

Using provide it is possible to have multiple potential providers for the same (generic) service (e.g. sendmail and qmail both provide a mta service), where only one actually provides the service. This may be used by service startup scripts which check for configuration files.

EXIT CODE
The exit code from need is 0 if the service was successfully started, 1 if the service failed badly, and 2 if the service is unavailable (i.e. disabled in configuration files). These exit codes reflect the exit codes from the service startup scripts.

The exit code from need -r is 0 if the service was successfully stopped, 1 if the service could not be stopped, and 2 if the service was not available to start with. The service shutdown scripts may only return 0 (for success) or 1 (for failure).

The exit code from provide is 0 if the service may be provided, 1 if it may not, and 2 if the parent process is not a child of init. It may block waiting for another provider which is initialising the service.

SIGNALS
initctl(8) uses SIGUSR1, SIGUSR2 and SIGPOLL for communication with simpleinit(8). Don't send these signals to it.

FILES
/dev/initctl
    This is the control FIFO, created by simpleinit(8), which initctl(8) writes commands to.

SEE ALSO
simpleinit(8), init(8)
A more complete discussion of the new boot script system, based on need(8), is available from: http://www.atnf.csiro.au/~rgooch/linux/boot-scripts/

AUTHOR
Richard Gooch (rgooch@atnf.csiro.au)

AVAILABILITY
The Util-Linux package is available from: ftp://ftp.??.kernel.org/pub/linux/utils/util-linux/