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  24 <a href="#libudev-udev-queue.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#libudev-udev-queue.description" class="shortcut">Description</a>
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  29 <div class="refentry">
  30 <a name="libudev-udev-queue"></a><div class="titlepage"></div>
  31 <div class="refnamediv"><table width="100%"><tr>
  32 <td valign="top">
  33 <h2><span class="refentrytitle"><a name="libudev-udev-queue.top_of_page"></a>udev_queue</span></h2>
  34 <p>udev_queue — access to currently active events</p>
  35 </td>
  36 <td valign="top" align="right"></td>
  37 </tr></table></div>
  38 <div class="refsynopsisdiv">
  39 <a name="libudev-udev-queue.synopsis"></a><h2>Synopsis</h2>
  40 <pre class="synopsis">struct              <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue">udev_queue</a>;
  41 struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * <a class="link" href="libudev-udev-queue.html#udev-queue-ref" title="udev_queue_ref ()">udev_queue_ref</a>                      (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  42 struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * <a class="link" href="libudev-udev-queue.html#udev-queue-unref" title="udev_queue_unref ()">udev_queue_unref</a>                    (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  43 struct <a class="link" href="libudev-udev.html#udev" title="struct udev"><span class="returnvalue">udev</span></a> *       <a class="link" href="libudev-udev-queue.html#udev-queue-get-udev" title="udev_queue_get_udev ()">udev_queue_get_udev</a>                 (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  44 struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * <a class="link" href="libudev-udev-queue.html#udev-queue-new" title="udev_queue_new ()">udev_queue_new</a>                      (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>);
  45 <span class="returnvalue">int</span>                 <a class="link" href="libudev-udev-queue.html#udev-queue-get-udev-is-active" title="udev_queue_get_udev_is_active ()">udev_queue_get_udev_is_active</a>       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  46 <span class="returnvalue">int</span>                 <a class="link" href="libudev-udev-queue.html#udev-queue-get-queue-is-empty" title="udev_queue_get_queue_is_empty ()">udev_queue_get_queue_is_empty</a>       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  47 <span class="returnvalue">int</span>                 <a class="link" href="libudev-udev-queue.html#udev-queue-get-seqnum-is-finished" title="udev_queue_get_seqnum_is_finished ()">udev_queue_get_seqnum_is_finished</a>   (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>,
  48                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> seqnum</code></em>);
  49 <span class="returnvalue">int</span>                 <a class="link" href="libudev-udev-queue.html#udev-queue-get-seqnum-sequence-is-finished" title="udev_queue_get_seqnum_sequence_is_finished ()">udev_queue_get_seqnum_sequence_is_finished</a>
  50                                                         (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>,
  51                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> start</code></em>,
  52                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> end</code></em>);
  53 struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> * <a class="link" href="libudev-udev-queue.html#udev-queue-get-queued-list-entry" title="udev_queue_get_queued_list_entry ()">udev_queue_get_queued_list_entry</a>
  54                                                         (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  55 unsigned long long <span class="returnvalue">int</span> <a class="link" href="libudev-udev-queue.html#udev-queue-get-kernel-seqnum" title="udev_queue_get_kernel_seqnum ()">udev_queue_get_kernel_seqnum</a>     (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  56 unsigned long long <span class="returnvalue">int</span> <a class="link" href="libudev-udev-queue.html#udev-queue-get-udev-seqnum" title="udev_queue_get_udev_seqnum ()">udev_queue_get_udev_seqnum</a>       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);
  57 </pre>
  58 </div>
  59 <div class="refsect1">
  60 <a name="libudev-udev-queue.description"></a><h2>Description</h2>
  61 <p>
  62 The udev daemon processes events asynchronously. All events which do not have
  63 interdependencies run in parallel. This exports the current state of the
  64 event processing queue, and the current event sequence numbers from the kernel
  65 and the udev daemon.
  66 </p>
  67 </div>
  68 <div class="refsect1">
  69 <a name="libudev-udev-queue.details"></a><h2>Details</h2>
  70 <div class="refsect2">
  71 <a name="udev-queue"></a><h3>struct udev_queue</h3>
  72 <pre class="programlisting">struct udev_queue;</pre>
  73 <p>
  74 Opaque object representing the current event queue in the udev daemon.
  75 </p>
  76 </div>
  77 <hr>
  78 <div class="refsect2">
  79 <a name="udev-queue-ref"></a><h3>udev_queue_ref ()</h3>
  80 <pre class="programlisting">struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * udev_queue_ref                      (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
  81 <p>
  82 Take a reference of a udev queue context.
  83 </p>
  84 <div class="variablelist"><table border="0" class="variablelist">
  85 <colgroup>
  86 <col align="left" valign="top">
  87 <col>
  88 </colgroup>
  89 <tbody>
  90 <tr>
  91 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
  92 <td>udev queue context</td>
  93 </tr>
  94 <tr>
  95 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
  96 <td>the same udev queue context.</td>
  97 </tr>
  98 </tbody>
  99 </table></div>
 100 </div>
 101 <hr>
 102 <div class="refsect2">
 103 <a name="udev-queue-unref"></a><h3>udev_queue_unref ()</h3>
 104 <pre class="programlisting">struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * udev_queue_unref                    (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 105 <p>
 106 Drop a reference of a udev queue context. If the refcount reaches zero,
 107 the resources of the queue context will be released.
 108 </p>
 109 <div class="variablelist"><table border="0" class="variablelist">
 110 <colgroup>
 111 <col align="left" valign="top">
 112 <col>
 113 </colgroup>
 114 <tbody>
 115 <tr>
 116 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 117 <td>udev queue context</td>
 118 </tr>
 119 <tr>
 120 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 121 <td>the passed queue context if it has still an active reference, or <span class="type">NULL</span> otherwise.</td>
 122 </tr>
 123 </tbody>
 124 </table></div>
 125 </div>
 126 <hr>
 127 <div class="refsect2">
 128 <a name="udev-queue-get-udev"></a><h3>udev_queue_get_udev ()</h3>
 129 <pre class="programlisting">struct <a class="link" href="libudev-udev.html#udev" title="struct udev"><span class="returnvalue">udev</span></a> *       udev_queue_get_udev                 (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 130 <p>
 131 Retrieve the udev library context the queue context was created with.
 132 </p>
 133 <div class="variablelist"><table border="0" class="variablelist">
 134 <colgroup>
 135 <col align="left" valign="top">
 136 <col>
 137 </colgroup>
 138 <tbody>
 139 <tr>
 140 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 141 <td>udev queue context</td>
 142 </tr>
 143 <tr>
 144 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 145 <td>the udev library context.</td>
 146 </tr>
 147 </tbody>
 148 </table></div>
 149 </div>
 150 <hr>
 151 <div class="refsect2">
 152 <a name="udev-queue-new"></a><h3>udev_queue_new ()</h3>
 153 <pre class="programlisting">struct <a class="link" href="libudev-udev-queue.html#udev-queue" title="struct udev_queue"><span class="returnvalue">udev_queue</span></a> * udev_queue_new                      (<em class="parameter"><code><span class="type">struct udev</span> *udev</code></em>);</pre>
 154 <p>
 155 The initial refcount is 1, and needs to be decremented to
 156 release the resources of the udev queue context.
 157 </p>
 158 <div class="variablelist"><table border="0" class="variablelist">
 159 <colgroup>
 160 <col align="left" valign="top">
 161 <col>
 162 </colgroup>
 163 <tbody>
 164 <tr>
 165 <td><p><span class="term"><em class="parameter"><code>udev</code></em> :</span></p></td>
 166 <td>udev library context</td>
 167 </tr>
 168 <tr>
 169 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 170 <td>the udev queue context, or <span class="type">NULL</span> on error.</td>
 171 </tr>
 172 </tbody>
 173 </table></div>
 174 </div>
 175 <hr>
 176 <div class="refsect2">
 177 <a name="udev-queue-get-udev-is-active"></a><h3>udev_queue_get_udev_is_active ()</h3>
 178 <pre class="programlisting"><span class="returnvalue">int</span>                 udev_queue_get_udev_is_active       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 179 <p>
 180 Check if udev is active on the system.
 181 </p>
 182 <div class="variablelist"><table border="0" class="variablelist">
 183 <colgroup>
 184 <col align="left" valign="top">
 185 <col>
 186 </colgroup>
 187 <tbody>
 188 <tr>
 189 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 190 <td>udev queue context</td>
 191 </tr>
 192 <tr>
 193 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 194 <td>a flag indicating if udev is active.</td>
 195 </tr>
 196 </tbody>
 197 </table></div>
 198 </div>
 199 <hr>
 200 <div class="refsect2">
 201 <a name="udev-queue-get-queue-is-empty"></a><h3>udev_queue_get_queue_is_empty ()</h3>
 202 <pre class="programlisting"><span class="returnvalue">int</span>                 udev_queue_get_queue_is_empty       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 203 <p>
 204 Check if udev is currently processing any events.
 205 </p>
 206 <div class="variablelist"><table border="0" class="variablelist">
 207 <colgroup>
 208 <col align="left" valign="top">
 209 <col>
 210 </colgroup>
 211 <tbody>
 212 <tr>
 213 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 214 <td>udev queue context</td>
 215 </tr>
 216 <tr>
 217 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 218 <td>a flag indicating if udev is currently handling events.</td>
 219 </tr>
 220 </tbody>
 221 </table></div>
 222 </div>
 223 <hr>
 224 <div class="refsect2">
 225 <a name="udev-queue-get-seqnum-is-finished"></a><h3>udev_queue_get_seqnum_is_finished ()</h3>
 226 <pre class="programlisting"><span class="returnvalue">int</span>                 udev_queue_get_seqnum_is_finished   (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>,
 227                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> seqnum</code></em>);</pre>
 228 <p>
 229 Check if udev is currently processing a given sequence number.
 230 </p>
 231 <div class="variablelist"><table border="0" class="variablelist">
 232 <colgroup>
 233 <col align="left" valign="top">
 234 <col>
 235 </colgroup>
 236 <tbody>
 237 <tr>
 238 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 239 <td>udev queue context</td>
 240 </tr>
 241 <tr>
 242 <td><p><span class="term"><em class="parameter"><code>seqnum</code></em> :</span></p></td>
 243 <td>sequence number</td>
 244 </tr>
 245 <tr>
 246 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 247 <td>a flag indicating if the given sequence number is currently active.</td>
 248 </tr>
 249 </tbody>
 250 </table></div>
 251 </div>
 252 <hr>
 253 <div class="refsect2">
 254 <a name="udev-queue-get-seqnum-sequence-is-finished"></a><h3>udev_queue_get_seqnum_sequence_is_finished ()</h3>
 255 <pre class="programlisting"><span class="returnvalue">int</span>                 udev_queue_get_seqnum_sequence_is_finished
 256                                                         (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>,
 257                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> start</code></em>,
 258                                                          <em class="parameter"><code>unsigned long long <span class="type">int</span> end</code></em>);</pre>
 259 <p>
 260 Check if udev is currently processing any events in a given sequence number range.
 261 </p>
 262 <div class="variablelist"><table border="0" class="variablelist">
 263 <colgroup>
 264 <col align="left" valign="top">
 265 <col>
 266 </colgroup>
 267 <tbody>
 268 <tr>
 269 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 270 <td>udev queue context</td>
 271 </tr>
 272 <tr>
 273 <td><p><span class="term"><em class="parameter"><code>start</code></em> :</span></p></td>
 274 <td>first event sequence number</td>
 275 </tr>
 276 <tr>
 277 <td><p><span class="term"><em class="parameter"><code>end</code></em> :</span></p></td>
 278 <td>last event sequence number</td>
 279 </tr>
 280 <tr>
 281 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 282 <td>a flag indicating if any of the sequence numbers in the given range is currently active.</td>
 283 </tr>
 284 </tbody>
 285 </table></div>
 286 </div>
 287 <hr>
 288 <div class="refsect2">
 289 <a name="udev-queue-get-queued-list-entry"></a><h3>udev_queue_get_queued_list_entry ()</h3>
 290 <pre class="programlisting">struct <a class="link" href="libudev-udev-list.html#udev-list-entry" title="struct udev_list_entry"><span class="returnvalue">udev_list_entry</span></a> * udev_queue_get_queued_list_entry
 291                                                         (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 292 <p>
 293 Get the first entry of the list of queued events.
 294 </p>
 295 <div class="variablelist"><table border="0" class="variablelist">
 296 <colgroup>
 297 <col align="left" valign="top">
 298 <col>
 299 </colgroup>
 300 <tbody>
 301 <tr>
 302 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 303 <td>udev queue context</td>
 304 </tr>
 305 <tr>
 306 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 307 <td>a udev_list_entry.</td>
 308 </tr>
 309 </tbody>
 310 </table></div>
 311 </div>
 312 <hr>
 313 <div class="refsect2">
 314 <a name="udev-queue-get-kernel-seqnum"></a><h3>udev_queue_get_kernel_seqnum ()</h3>
 315 <pre class="programlisting">unsigned long long <span class="returnvalue">int</span> udev_queue_get_kernel_seqnum     (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 316 <p>
 317 Get the current kernel event sequence number.
 318 </p>
 319 <div class="variablelist"><table border="0" class="variablelist">
 320 <colgroup>
 321 <col align="left" valign="top">
 322 <col>
 323 </colgroup>
 324 <tbody>
 325 <tr>
 326 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 327 <td>udev queue context</td>
 328 </tr>
 329 <tr>
 330 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 331 <td>the sequence number.</td>
 332 </tr>
 333 </tbody>
 334 </table></div>
 335 </div>
 336 <hr>
 337 <div class="refsect2">
 338 <a name="udev-queue-get-udev-seqnum"></a><h3>udev_queue_get_udev_seqnum ()</h3>
 339 <pre class="programlisting">unsigned long long <span class="returnvalue">int</span> udev_queue_get_udev_seqnum       (<em class="parameter"><code><span class="type">struct udev_queue</span> *udev_queue</code></em>);</pre>
 340 <p>
 341 Get the last known udev event sequence number.
 342 </p>
 343 <div class="variablelist"><table border="0" class="variablelist">
 344 <colgroup>
 345 <col align="left" valign="top">
 346 <col>
 347 </colgroup>
 348 <tbody>
 349 <tr>
 350 <td><p><span class="term"><em class="parameter"><code>udev_queue</code></em> :</span></p></td>
 351 <td>udev queue context</td>
 352 </tr>
 353 <tr>
 354 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 355 <td>the sequence number.</td>
 356 </tr>
 357 </tbody>
 358 </table></div>
 359 </div>
 360 </div>
 361 </div>
 362 <div class="footer">
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