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diff --git a/man/sd_is_fifo.xml b/man/sd_is_fifo.xml new file mode 100644 index 0000000000..595c8f112d --- /dev/null +++ b/man/sd_is_fifo.xml @@ -0,0 +1,217 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> + +<!-- + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +--> + +<refentry id="sd_is_fifo"> + + <refentryinfo> + <title>sd_is_fifo</title> + <productname>systemd</productname> + + <authorgroup> + <author> + <contrib>Developer</contrib> + <firstname>Lennart</firstname> + <surname>Poettering</surname> + <email>lennart@poettering.net</email> + </author> + </authorgroup> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_is_fifo</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_is_fifo</refname> + <refname>sd_is_socket</refname> + <refname>sd_is_socket_inet</refname> + <refname>sd_is_socket_unix</refname> + <refname>sd_is_mq</refname> + <refpurpose>Check the type of a file descriptor</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-daemon.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_is_fifo</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_is_socket</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>family</parameter></paramdef> + <paramdef>int <parameter>type</parameter></paramdef> + <paramdef>int <parameter>listening</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_is_socket_inet</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>family</parameter></paramdef> + <paramdef>int <parameter>type</parameter></paramdef> + <paramdef>int <parameter>listening</parameter></paramdef> + <paramdef>uint16_t <parameter>port</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_is_socket_unix</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>type</parameter></paramdef> + <paramdef>int <parameter>listening</parameter></paramdef> + <paramdef>const char* <parameter>path</parameter></paramdef> + <paramdef>size_t <parameter>length</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_is_mq</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_is_fifo()</function> may be called + to check whether the specified file descriptor refers + to a FIFO or pipe. If the <parameter>path</parameter> + parameter is not NULL, it is checked whether the FIFO + is bound to the specified file system path.</para> + + <para><function>sd_is_socket()</function> may be + called to check whether the specified file descriptor + refers to a socket. If the + <parameter>family</parameter> parameter is not + AF_UNSPEC it is checked whether the socket is of the + specified family (AF_UNIX, AF_INET, ...). If the + <parameter>type</parameter> parameter is not 0 it is + checked whether the socket is of the specified type + (SOCK_STREAM, SOCK_DGRAM, ...). If the + <parameter>listening</parameter> parameter is positive + it is checked whether the socket is in accepting mode, + i.e. <function>listen()</function> has been called for + it. If <parameter>listening</parameter> is 0, it is + checked whether the socket is not in this mode. If the + parameter is negative, no such check is made. The + <parameter>listening</parameter> parameter should only + be used for stream sockets and should be set to a + negative value otherwise.</para> + + <para><function>sd_is_socket_inet()</function> is + similar to <function>sd_is_socket()</function>, but + optionally checks the IPv4 or IPv6 port number the + socket is bound to, unless <parameter>port</parameter> + is zero. For this call <parameter>family</parameter> + must be passed as either AF_UNSPEC, AF_INET, or + AF_INET6.</para> + + <para><function>sd_is_socket_unix()</function> is + similar to <function>sd_is_socket()</function>, but + optionally checks the AF_UNIX path the socket is bound + to, unless the <parameter>path</parameter> parameter + is NULL. For normal file system AF_UNIX sockets set + the <parameter>length</parameter> parameter to 0. For + Linux abstract namespace sockets set the + <parameter>length</parameter> to the size of the + address, including the initial 0 byte and set + <parameter>path</parameter> to the initial 0 byte of + the socket address.</para> + + <para><function>sd_is_mq()</function> may be called to + check whether the specified file descriptor refers to + a POSIX message queue. If the + <parameter>path</parameter> parameter is not NULL, it + is checked whether the message queue is bound to the + specified name.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On failure, these calls return a negative + errno-style error code. If the file descriptor is of + the specified type and bound to the specified address + a positive return value is returned, otherwise + zero.</para> + </refsect1> + + <refsect1> + <title>Notes</title> + + <para>These functions are provided by the reference + implementation of APIs for new-style daemons and + distributed with the systemd package. The algorithms + they implement are simple, and can easily be + reimplemented in daemons if it is important to support + this interface without using the reference + implementation.</para> + + <para>Internally, these function use a combination of + <filename>fstat()</filename> and + <filename>getsockname()</filename> to check the file + descriptor type and where it is bound to.</para> + + <para>For details about the algorithms check the + liberally licensed reference implementation sources: + <ulink url="http://cgit.freedesktop.org/systemd/systemd/plain/src/libsystemd-daemon/sd-daemon.c"/> + and <ulink + url="http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-daemon.h"/></para> + + <para><function>sd_is_fifo()</function> and the + related functions are implemented in the reference + implementation's <filename>sd-daemon.c</filename> and + <filename>sd-daemon.h</filename> files. These + interfaces are available as shared library, which can + be compiled and linked to with the + <literal>libsystemd-daemon</literal> + <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry> + file. Alternatively, applications consuming these APIs + may copy the implementation into their source + tree. For more details about the reference + implementation see + <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> + + <para>These functions continue to work as described, + even if -DDISABLE_SYSTEMD is set during + compilation.</para> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |