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<?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">
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<!-- SPDX - License - Identifier: LGPL - 2.1 - or - later -->
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<refentry id= "sd_bus_can_send"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo >
<title > sd_bus_can_send</title>
<productname > systemd</productname>
</refentryinfo>
<refmeta >
<refentrytitle > sd_bus_can_send</refentrytitle>
<manvolnum > 3</manvolnum>
</refmeta>
<refnamediv >
<refname > sd_bus_can_send</refname>
<refpurpose > Check which types can be sent over a bus object</refpurpose>
</refnamediv>
<refsynopsisdiv >
<funcsynopsis >
<funcsynopsisinfo > #include < systemd/sd-bus.h> </funcsynopsisinfo>
<funcprototype >
<funcdef > void <function > sd_bus_can_send</function> </funcdef>
<paramdef > sd_bus *<parameter > bus</parameter> </paramdef>
<paramdef > char <parameter > type</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 >
<title > Description</title>
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<para > <function > sd_bus_can_send()</function> is mostly used for checking if file descriptor
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passing is available on the given bus. <parameter > type</parameter> can be any of the
<constant > SD_BUS_TYPE</constant> constants.</para>
</refsect1>
<refsect1 >
<title > Return Value</title>
<para > On failure, <function > sd_bus_can_send()</function> returns a negative errno-style error
code. If values of the given type can be sent over the given bus, it returns a positive integer.
Otherwise, it returns zero.</para>
<refsect2 >
<title > Errors</title>
<para > Returned errors may indicate the following problems:</para>
<variablelist >
<varlistentry >
<term > <constant > -ENOPKG</constant> </term>
<listitem > <para > The bus object <parameter > bus</parameter> could not be resolved.</para>
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<xi:include href= "version-info.xml" xpointer= "v246" />
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</listitem>
</varlistentry>
<varlistentry >
<term > <constant > -ENOTCONN</constant> </term>
<listitem > <para > The input parameter <parameter > bus</parameter> is
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<constant > NULL</constant> or the bus is not connected.</para>
<xi:include href= "version-info.xml" xpointer= "v246" /> </listitem>
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</varlistentry>
<varlistentry >
<term > <constant > -ECHILD</constant> </term>
<listitem > <para > The bus object <parameter > bus</parameter> was created in a different
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process.</para>
<xi:include href= "version-info.xml" xpointer= "v246" /> </listitem>
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</varlistentry>
</variablelist>
</refsect2>
</refsect1>
<xi:include href= "libsystemd-pkgconfig.xml" />
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<refsect1 >
<title > History</title>
<para > <function > sd_bus_can_send()</function> was added in version 246.</para>
</refsect1>
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<refsect1 >
<title > See Also</title>
<para >
<citerefentry > <refentrytitle > systemd</refentrytitle> <manvolnum > 1</manvolnum> </citerefentry> ,
<citerefentry > <refentrytitle > sd-bus</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry>
</para>
</refsect1>
</refentry>