add some documentation for the init scripts

SVN-Revision: 5140
This commit is contained in:
Felix Fietkau 2006-10-15 23:37:53 +00:00
parent 75c1f29021
commit 00818780b4
2 changed files with 62 additions and 0 deletions

61
docs/init-scripts.tex Normal file
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Because OpenWrt uses its own init script system, all init scripts must be installed
as \texttt{/etc/init.d/\textit{name}} use \texttt{/etc/rc.common} as a wrapper.
Example: \texttt{/etc/init.d/httpd}
\begin{Verbatim}
#!/bin/sh /etc/rc.common
# Copyright (C) 2006 OpenWrt.org
START=50
start() {
[ -d /www ] && httpd -p 80 -h /www -r OpenWrt
}
stop() {
killall httpd
}
\end{Verbatim}
as you can see, the script does not actually parse the command line arguments itself.
This is done by the wrapper script \texttt{/etc/rc.common}.
\texttt{start()} and \texttt{stop()} are the basic functions, which almost any init
script should provide. \texttt{start()} is called when the user runs \texttt{/etc/init.d/httpd start}
or (if the script is enabled and does not override this behavior) at system boot time.
Enabling and disabling init scripts is done by running \texttt{/etc/init.d/\textit{name} start}
or \texttt{/etc/init.d/\textit{name} stop}. This creates or removes symbolic links to the
init script in \texttt{/etc/rc.d}, which is processed by \texttt{/etc/init.d/rcS} at boot time.
The order in which these scripts are run is defined in the variable \texttt{START} in the init
script, which is optional and defaults to \texttt{50}. Changing it requires running
\texttt{/etc/init.d/\textit{name} enable} again.
You can also override these standard init script functions:
\begin{itemize}
\item \texttt{boot()} \\
Commands to be run at boot time. Defaults to \texttt{start()}
\item \texttt{restart()} \\
Restart your service. Defaults to \texttt{stop(); start()}
\item \texttt{reload()} \\
Reload the configuration files for your service. Defaults to \texttt{restart()}
\end{itemize}
You can also add custom commands by creating the appropriate functions and referencing them
in the \texttt{EXTRA\_COMMANDS} variable. Helptext is added in \texttt{EXTRA\_HELP}.
Example:
\begin{Verbatim}
status() {
# print the status info
}
EXTRA_COMMANDS="status"
EXTRA_HELP=" status Print the status of the service"
\end{Verbatim}

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\subsection{Hotplug}
\subsection{Init scripts}
\include{init-scripts}
\subsection{Network scripts}
\include{network-scripts}