projects / systemd.git / blame
| Commit | Line | Data |
|---|---|---|
| 60f067b4 JS |
1 | <html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>sd_bus_request_name</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><style> |
| 2 | a.headerlink { | |
| 3 | color: #c60f0f; | |
| 4 | font-size: 0.8em; | |
| 5 | padding: 0 4px 0 4px; | |
| 6 | text-decoration: none; | |
| 7 | visibility: hidden; | |
| 8 | } | |
| 9 | ||
| 10 | a.headerlink:hover { | |
| 11 | background-color: #c60f0f; | |
| 12 | color: white; | |
| 13 | } | |
| 14 | ||
| 15 | h1:hover > a.headerlink, h2:hover > a.headerlink, h3:hover > a.headerlink, dt:hover > a.headerlink { | |
| 16 | visibility: visible; | |
| 17 | } | |
| 18 | </style><a href="index.html">Index </a>· | |
| 19 | <a href="systemd.directives.html">Directives </a>· | |
| 20 | <a href="../python-systemd/index.html">Python </a>· | |
| 21 | <a href="../libudev/index.html">libudev </a>· | |
| e735f4d4 MP |
22 | <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 219</span><hr><div class="refentry"><a name="sd_bus_request_name"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_bus_request_name, sd_bus_release_name — Request or release a well-known name on a bus</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-bus.h></pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_bus_request_name</b>(</code></td><td>sd_bus *<var class="pdparam">bus</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">name</var>, </td></tr><tr><td> </td><td>uint64_t <var class="pdparam">flags</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_bus_release_name</b>(</code></td><td>sd_bus *<var class="pdparam">bus</var>, </td></tr><tr><td> </td><td>const char *<var class="pdparam">name</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm139697602185728"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_bus_request_name()</code> requests a |
| 23 | well-known name on a bus. It takes a bus connection, a valid bus | |
| 24 | name and a flags parameter. The flags parameter is a combination | |
| 25 | of the following flags:</p><div class="variablelist"><dl class="variablelist"><dt id="SD_BUS_NAME_ALLOW_REPLACEMENT"><span class="term"><code class="varname">SD_BUS_NAME_ALLOW_REPLACEMENT</code></span><a class="headerlink" title="Permalink to this term" href="#SD_BUS_NAME_ALLOW_REPLACEMENT">¶</a></dt><dd><p>After acquiring the name successfully, permit | |
| 26 | other peers to take over the name when they try to acquire it | |
| 27 | with the <code class="varname">SD_BUS_NAME_REPLACE_EXISTING</code> flag | |
| 28 | set. If <code class="varname">SD_BUS_NAME_ALLOW_REPLACEMENT</code> is | |
| 29 | not set on the original request, such a request by other peers | |
| 30 | will be denied.</p></dd><dt id="SD_BUS_NAME_REPLACE_EXISTING"><span class="term"><code class="varname">SD_BUS_NAME_REPLACE_EXISTING</code></span><a class="headerlink" title="Permalink to this term" href="#SD_BUS_NAME_REPLACE_EXISTING">¶</a></dt><dd><p>Take over the name if it is already acquired | |
| 31 | by another peer, and that other peer has permitted takeover by | |
| 32 | setting <code class="varname">SD_BUS_NAME_ALLOW_REPLACEMENT</code> while | |
| 33 | acquiring it.</p></dd><dt id="SD_BUS_NAME_QUEUE"><span class="term"><code class="varname">SD_BUS_NAME_QUEUE</code></span><a class="headerlink" title="Permalink to this term" href="#SD_BUS_NAME_QUEUE">¶</a></dt><dd><p>Queue the acquisition of the name when the | |
| 34 | name is already taken.</p></dd></dl></div><p><code class="function">sd_bus_release_name()</code> releases an | |
| 35 | acquired well-known name. It takes a bus connection and a valid | |
| 36 | bus name as parameters.</p></div><div class="refsect1"><a name="idm139697602176208"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>On success, these calls return 0 or a positive integer. On | |
| 37 | failure, these calls return a negative errno-style error | |
| 38 | code.</p><p>If <code class="varname">SD_BUS_NAME_QUEUE</code> is specified, | |
| 39 | <code class="function">sd_bus_request_name()</code> will return 0 when the | |
| 40 | name is already taken by another peer and the client has been | |
| 41 | added to the queue for the name. In that case, the caller can | |
| 42 | subscribe to "<code class="literal">NameOwnerChanged</code>" signals to be | |
| 43 | notified when the name is successfully acquired. | |
| 44 | <code class="function">sd_bus_request_name()</code> returns > 0 when the | |
| 45 | name has immediately been acquired successfully.</p></div><div class="refsect1"><a name="idm139697602171600"></a><h2 id="Errors">Errors<a class="headerlink" title="Permalink to this headline" href="#Errors">¶</a></h2><p>Returned errors may indicate the following problems:</p><div class="variablelist"><dl class="variablelist"><dt id="-EALREADY"><span class="term"><code class="constant">-EALREADY</code></span><a class="headerlink" title="Permalink to this term" href="#-EALREADY">¶</a></dt><dd><p>The caller already is the owner of the | |
| 46 | specified name.</p></dd><dt id="-EEXIST"><span class="term"><code class="constant">-EEXIST</code></span><a class="headerlink" title="Permalink to this term" href="#-EEXIST">¶</a></dt><dd><p>The name has already been acquired by a | |
| 47 | different peer, and SD_BUS_NAME_REPLACE_EXISTING was not | |
| 48 | specified or the other peer did not specify | |
| 49 | SD_BUS_NAME_ALLOW_REPLACEMENT while acquiring the | |
| 50 | name.</p></dd><dt id="-ESRCH"><span class="term"><code class="constant">-ESRCH</code></span><a class="headerlink" title="Permalink to this term" href="#-ESRCH">¶</a></dt><dd><p>It was attempted to release a name that is | |
| 51 | currently not registered on the bus.</p></dd><dt id="-EADDRINUSE"><span class="term"><code class="constant">-EADDRINUSE</code></span><a class="headerlink" title="Permalink to this term" href="#-EADDRINUSE">¶</a></dt><dd><p>It was attempted to release a name that is | |
| 52 | owned by a different peer on the bus.</p></dd><dt id="-EINVAL"><span class="term"><code class="constant">-EINVAL</code></span><a class="headerlink" title="Permalink to this term" href="#-EINVAL">¶</a></dt><dd><p>A specified parameter is | |
| 53 | invalid.</p></dd><dt id="-ENOTCONN"><span class="term"><code class="constant">-ENOTCONN</code></span><a class="headerlink" title="Permalink to this term" href="#-ENOTCONN">¶</a></dt><dd><p>The bus connection has been | |
| 54 | disconnected.</p></dd><dt id="-ECHILD"><span class="term"><code class="constant">-ECHILD</code></span><a class="headerlink" title="Permalink to this term" href="#-ECHILD">¶</a></dt><dd><p>The bus connection has been created in a | |
| 55 | different process than the current one.</p></dd></dl></div></div><div class="refsect1"><a name="idm139697606062224"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_bus_acquire_name()</code> and | |
| 56 | <code class="function">sd_bus_release_name()</code> interfaces are | |
| 57 | available as a shared library, which can be compiled and linked to | |
| 58 | with the | |
| 59 | <code class="constant">libsystemd</code> <a href="http://linux.die.net/man/1/pkg-config"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a> | |
| 60 | file.</p></div><div class="refsect1"><a name="idm139697606057824"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p> | |
| 61 | <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>, | |
| 62 | <a href="sd-bus.html"><span class="citerefentry"><span class="refentrytitle">sd-bus</span>(3)</span></a>, | |
| 63 | <a href="sd_bus_new.html"><span class="citerefentry"><span class="refentrytitle">sd_bus_new</span>(3)</span></a> | |
| 64 | </p></div></div></body></html> |