diff options
Diffstat (limited to 'man/sd_bus_set_watch_bind.xml')
| -rw-r--r-- | man/sd_bus_set_watch_bind.xml | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/man/sd_bus_set_watch_bind.xml b/man/sd_bus_set_watch_bind.xml new file mode 100644 index 0000000..20f6f53 --- /dev/null +++ b/man/sd_bus_set_watch_bind.xml @@ -0,0 +1,118 @@ +<?xml version='1.0'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="sd_bus_set_watch_bind" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_set_watch_bind</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_set_watch_bind</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_set_watch_bind</refname> + <refname>sd_bus_get_watch_bind</refname> + + <refpurpose>Control socket binding watching on bus connections</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_set_watch_bind</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>int <parameter>b</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_get_watch_bind</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_bus_set_watch_bind()</function> may be used to enable or disable client-side watching of server + socket binding for a bus connection object. If the <parameter>b</parameter> is true, the feature is enabled, + otherwise disabled (which is the default). When enabled, and the selected bus address refers to an + <filename>AF_UNIX</filename> socket in the file system which does not exist while the connection attempt is made an + <citerefentry project='man-pages'><refentrytitle>inotify</refentrytitle><manvolnum>7</manvolnum></citerefentry> watch is installed on + it, waiting for the socket to appear. As soon as the socket appears the connection is made. This functionality is + useful in particular in early-boot programs that need to run before the system bus is available, but want to + connect to it the instant it may be connected to.</para> + + <para><function>sd_bus_get_watch_bind()</function> may be used to query the current setting of this feature. It + returns zero when the feature is disabled, and positive if enabled.</para> + + <para>Note that no timeout is applied while we wait for the socket to appear. This means that any + synchronous remote operation (such as + <citerefentry><refentrytitle>sd_bus_call</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry> or + <citerefentry><refentrytitle>sd_bus_request_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>), + that is used on a connection with this feature enabled that hasn't been established yet, might block + forever if the socket is never created. However, asynchronous remote operations (such as + <citerefentry><refentrytitle>sd_bus_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_call_async</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_add_match_async</refentrytitle><manvolnum>3</manvolnum></citerefentry>) + do not block in this case, and safely enqueue the requested operations to be dispatched the instant the + connection is set up.</para> + + <para>Use <citerefentry><refentrytitle>sd_bus_is_ready</refentrytitle><manvolnum>3</manvolnum></citerefentry> to + determine whether the connection is fully established, i.e. whether the peer socket has been bound, connected to + and authenticated. Use + <citerefentry><refentrytitle>sd_bus_set_connected_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry> to + be notified when the connection is fully established.</para> + + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On success, these functions return 0 or a positive integer. On failure, they return a negative + errno-style error code.</para> + + <refsect2> + <title>Errors</title> + + <para>Returned errors may indicate the following problems:</para> + + <variablelist> + <varlistentry> + <term><constant>-ECHILD</constant></term> + + <listitem><para>The bus connection has been created in a different process.</para></listitem> + </varlistentry> + </variablelist> + </refsect2> + </refsect1> + + <xi:include href="libsystemd-pkgconfig.xml" /> + + <refsect1> + <title>See Also</title> + + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>inotify</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_call</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_request_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_is_ready</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_set_connected_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |