--- /dev/null
+.TH DINIT "1" "June 2017" "Dinit 0.06" "Dinit \- service management system"
+.SH NAME
+dinit \- supervise processes and manage services
+.\"
+.SH SYNOPSIS
+.\"
+.B dinit
+[\-s] [\-d \fIdir\fR] [\-p \fIpath\fR] [\fIservice-name\fR]
+.\"
+.SH DESCRIPTION
+.\"
+\fBDinit\fR is a process supervisor and service manager which can also
+function as a system \fBinit\fR process. It has a small but functional
+feature set, offering service dependency handling, parallel startup,
+automatic rate-limited restart of failing processes, and service control
+functions.
+.LP
+Dinit reads service descriptions from files located in the service
+description directory, normally \fI/etc/dinit.d\fR for the system instance
+or \fI$HOME/dinit.d\fR when run as a user process. See \fBSERVICE
+DESCRIPTION FILES\fR for details.
+.\"
+.SH OPTIONS
+.TP
+\fB\-d\fR \fIdir\fP, \fB\-\-services\-dir\fR \fIdir\fP
+Specifies \fIdir\fP as the directory containing service definition files.
+.TP
+\fB\-p\fR \fIpath\fP, \fB\-\-socket-path\fR \fIpath\fP
+Species \fIpath\fP as the path to the control socket used to listen for
+commands from the \fBdinitctl\fR program.
+.TP
+\fB\-s\fR, \fB\-\-system\fR
+Run as the system init process. This is the default if invoked as PID 1.
+This option affects the default service definition directory and
+control socket path.
+.TP
+\fB\-\-help\fR
+display this help and exit
+.TP
+\fIservice-name\fR
+Specifies the name of the service that should be started (along with its
+dependencies). If not specified, defaults to \fIboot\fR (which requires
+that a suitable service description for the \fIboot\fR service exists).
+.\"
+.SH SERVICE DESCRIPTION FILES
+.\"
+Service description files specify the various attributes of a service. A
+service description file is named after the service it represents, and is
+a plain-text file with simple key-value format. The description files are
+located in the service description directory (which defaults to
+\fI/etc/dinit.d\fR for the system process).
+.LP
+All services have a \fItype\fR and a set of \fIdependencies\fR. Service
+types are discussed in the following subsection. If a service depends on
+another service, then starting the first service causes the second to start
+also (and the second service must complete its startup before the first
+is considered started). Similarly, if one service depends on another which
+becomes stopped, the first service must also stop.
+.LP
+Service description files are read by Dinit on an "as needed" basis. Once a
+service description has been read there is no way (yet) to alter it.
+.\"
+.SS SERVICE TYPES
+.\"
+There are four basic types of service:
+.IP \(bu
+\fBProcess\fR services. This kind of service runs as a single process; starting
+the service simply requires starting the process; stopping the service is
+accomplished by stopping the process (via sending it a signal).
+.IP \(bu
+\fBBgprocess\fR services ("background process" services). This kind of
+service is similar to a regular process service, but the process daemonizes
+or otherwise forks from the original process which starts it, and the
+process ID is written to a file. Dinit can read the process ID from the
+file and, if it is running as the system init process, can supervise it.
+.IP \(bu
+\fBScripted\fR services are services which are started and stopped by a
+command (which need not actually be a script, despite the name). They can
+not be supervised.
+.IP \(bu
+\fBInternal\fR services do not run as an external process at all. They can
+be started and stopped without any external action. They are useful for
+grouping other services (via service dependencies).
+.\"
+.SS SERVICE PROPERTIES
+.\"
+This section described the various service properties that can be specified
+in a service description file. Each line of the file can specify a single
+property value, expressed as "\fIproperty-name\fR = \fIvalue\fR". Comments
+begin with a hash mark (#) and extend to the end of the line (they must be
+separated from setting values by at least one whitespace character). Values
+are interpreted literally, except that:
+.\"
+.IP \(bu
+White space (comprised of spaces, tabs, etc) is collapsed to a single space.
+.IP \(bu
+Double quotes (") can be used around all or part of a property value, to
+prevent whitespace collapse and prevent interpretation of other special
+characters (such as "#") inside the quotes. The quote characters are not
+considered part of the parameter value.
+.IP \(bu
+A backslash (\\) can be used to escape the next character, causing it to
+lose any special meaning and become part of the property value. A double
+backslash (\\\\) is collapsed to a single backslash within the parameter
+value.
+.LP
+The following properties can be specified:
+.TP
+\fBtype\fR = {process | bgprocess | scripted | internal}
+Specifies the service type.
+.TP
+\fBcommand\fR = \fIcommand-string\fR
+Specifies the command, including command-line arguments, for starting the
+process. Applies only to \fBprocess\fR, \fBbgprocess\fR and \fBscripted\fR
+services.
+.TP
+\fBstop\-command\fR = \fIcommand-string\fR
+Specifies the command to stop the service. Applicable only to \fBscripted\fR
+services.
+.TP
+\fBrestart\fR = {yes | true | no | false}
+Indicates whether the service should automatically restart if it stops for
+any reason (including unexpected process termination, service dependency
+stopping, or user-initiated service stop).
+.TP
+\fBsmooth-recovery\fR = {yes | true | no | false}
+Applies only to \fBprocess\fR and \fBbgprocess\fR services. When set true/yes,
+an automatic process restart can be performed without first stopping any
+dependent services. This setting is meaningless if the \fBrestart\fR setting
+is set to false.
+.TP
+\fBrestart-delay\fR = \fIXXX.YYYY\fR
+Specifies the minimum time between automatic restarts. Enforcing a sensible
+minimum prevents Dinit from consuming a large number of process cycles in
+case a process continuously fails immediately after it is started. The
+default is 0.2 (200 milliseconds).
+.TP
+\fBrestart-limit-interval\fR = \fIXXX.YYYY\fR
+Sets the interval, in seconds, over which restarts are limited. If a process
+automatically restarts more than a certain number of times (specified by the
+\fBrestart-limit-count\fR setting) in this time interval, it will not restart
+again. The default value is 10 seconds.
+.TP
+\fBrestart-limit-count\fR = \fINNN\fR
+Specifies the maximum number of times that a service can automatically restart
+over the interval specified by \fBrestart-limit-interval\fR. Specify a value
+of 0 to disable the restart limit.
+.TP
+\fBpid-file\fR = \fIpath-to-file\fR
+For \fBbgprocess\fR type services only; specifies the path of the file where
+daemon will write its process ID before detaching. Dinit will read the
+contents of this file when starting the service, once the initial process
+exits, will supervise the process with the discovered process ID, and may
+send signals to the process ID to stop the service; if Dinit runs as a
+privileged user the path should therefore not be writable by unprivileged
+users.
+.TP
+\fBdepends-on\fR = \fIservice-name\fR
+This service depends on the named service. Starting this service will start
+the named service; the command to start this service will not be executed
+until the named service has started. If the named service is stopped then
+this service will also be stopped.
+.TP
+\fBwaits-for\fR = \fIservice-name\fR
+When this service is started, wait for the named service to finish starting
+(or to fail starting) before commencing the start procedure for this service.
+Starting this service will automatically start the named service. If the
+named service fails to start, this service will start as usual (subject to
+other dependencies being met).
+.TP
+\fBsocket-listen\fR = \fIsocket-path\fR
+Pre-open a socket for the service and pass it to the service using the
+\fBsystemd\fR activation protocol. This by itself does not give so called
+"socket activation", but does allow that any process trying to connect to the
+specified socket will be able to do so, even before the service is properly
+prepared to accept connections.
+.TP
+\fBsocket-permissions\fR = \fIoctal-permissions-mask\fR
+Gives the permissions for the socket specified using \fBsocket-listen\fR.
+Normally this will be 600 (user access only), 660 (user and group
+access), or 666 (all users). The default is 666.
+.TP
+\fBsocket-uid\fR = {\fInumeric-user-id\fR | \fIusername\fR}
+Specifies the user that should own the activation socket. If
+\fBsocket-uid\fR is specified without also specifying \fBsocket-gid\fR, then
+the socket group is the primary group of the specified user (as found in the
+system user database, normally \fI/etc/passwd\fR). If the socket owner is not
+specified, the socket will be owned by the user id of the Dinit process.
+.TP
+\fBsocket-gid\fR = {\fInumeric-group-id\fR | \fIgroup-name\fR}
+Specifies the group of the activation socket. See discussion of
+\fBsocket-uid\fR.
+.TP
+\fBtermsignal\fR = {HUP | INT | QUIT | USR1 | USR2}
+Specifies an additional signal to send to the process when requesting it
+to terminate (applies to 'process' services only). SIGTERM is always
+sent along with the specified signal, unless the \fBnosigterm\fR option is
+specified via the \fBoptions\fR parameter.
+.TP
+\fBoptions\fR = {runs\-on\-console | nosigterm | starts\-rwfs | starts\-log}...
+Specifies various options for this service:
+.RS
+.TP
+\fBno-sigterm\fR
+specifies that the TERM signal should not be send to the process to terminate
+it. (Another signal can be specified using the \fBtermsignal\fR setting; if no
+other signal is specified, no signal will be sent, which usually means that
+the service will not terminate).
+.TP
+\fBruns-on-console\fR
+specifies that this service uses the console; its input and output should be
+directed to the console (or precisely, to the device to which Dinit's standard
+output stream is connected). A service running on the console prevents other
+services from running on the console (they will queue for the console).
+
+The \fIinterrupt\fR key (normally control-C) will be active for process / scripted
+services that run on the console. Handling of an interrupt is determined by
+the service process, but typically will cause it to terminate.
+.TP
+\fBstarts-on-console\fR
+specifies that this service uses the console during service startup. This is
+implied by \fBruns-on-console\fR, but can be specified separately for services
+that need the console while they start but not afterwards.
+
+This setting is not applicable to regular \fBprocess\fR services, but can be
+used for \fBscripted\fR and \fBbgprocess\fR services. It allows for
+interrupting startup via the \fIinterrupt\fR key (normally control-C). This is
+useful to allow filesystem checks to be interrupted/skipped.
+.TP
+\fBstarts-rwfs\fR
+this service mounts the root filesystem read/write (or at least mounts the
+normal writable filesystems for the system). This prompts Dinit to create its
+control socket, if it has not already managed to do so.
+.TP
+\fBstarts-log\fR
+this service starts the system log daemon. Dinit will begin logging via the
+\fI/dev/log\fR socket.
+.TP
+\fBpass-cs-fd\fR
+pass an open Dinit control socket to the process when launching it (the
+\fIDINIT_CS_FD\fR environment variable will be set to the file descriptor of
+the socket). This allows the service to issue commands to Dinit even if the
+regular control socket is not available yet.
+
+Using this option has security implications! The service which receives the
+control socket must close it before launching any untrusted processes. You
+should not use this option unless the service is designed to receive a Dinit
+control socket.
+.RE
+.TP
+\fBlogfile\fR = \fIlog-file-path\fR
+Specifies the log file for the service. Output from the service process
+will go this file.
+.LP
+The next section contains example service descriptions including some of the
+parameters and options described above.
+.\"
+.SS EXAMPLES
+.LP
+Here is an example service description for the \fBmysql\fR database server.
+It has a dependency on the \fBrcboot\fR service (not shown) which is
+expected to have set up the system to a level suitable for basic operation.
+
+.RS
+.nf
+.gcolor yellow
+# mysqld service
+type = process
+command = /usr/bin/mysqld --user=mysql
+logfile = /var/log/mysqld.log
+smooth-recovery = true
+restart = false
+depends-on = rcboot # Basic system services must be ready
+.gcolor
+.RE
+.fi
+.LP
+Here is an examples for a filesystem check "service", run by a script
+(\fI/etc/dinit.d/rootfscheck.sh\fR). The script may need to reboot the
+system, but the control socket may not have been created, so it uses the
+\fBpass-cs-fd\fR option to allow the \fBreboot\fR command to issue control
+commands to Dinit. It runs on the console, so that output is visible and
+the process can be interrupted using control-C.
+
+.RS
+.nf
+.gcolor yellow
+# rootfscheck service
+type = scripted
+command = /etc/dinit.d/rootfscheck.sh
+restart = false
+options = starts-on-console pass-cs-fd
+depends-on = early-filesystems # /proc and /dev
+depends-on = device-node-daemon
+.gcolor
+.fi
+.RE
+
+More examples are provided with the Dinit distribution.
+.\"
+.SH AUTHOR
+Dinit, and this manual, were written by Davin McCall.
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