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</div><hr /><div id="ev.examples" class="chapter">
<h1>Examples</h1>
<div class="example" id="example-3610">
<p><strong>Example #1 Simple timers</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Create and start timer firing after 2 seconds<br /></span><span style="color: #0000BB">$w1 </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, function () {<br /> echo </span><span style="color: #DD0000">"2 seconds elapsed\n"</span><span style="color: #007700">;<br />});<br /><br /></span><span style="color: #FF8000">// Create and launch timer firing after 2 seconds repeating each second<br />// until we manually stop it<br /></span><span style="color: #0000BB">$w2 </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"is called every second, is launched after 2 seconds\n"</span><span style="color: #007700">;<br /> echo </span><span style="color: #DD0000">"iteration = "</span><span style="color: #007700">, </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">iteration</span><span style="color: #007700">(), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;<br /><br /> </span><span style="color: #FF8000">// Stop the watcher after 5 iterations<br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">iteration</span><span style="color: #007700">() == </span><span style="color: #0000BB">5 </span><span style="color: #007700">and </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /> </span><span style="color: #FF8000">// Stop the watcher if further calls cause more than 10 iterations<br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">iteration</span><span style="color: #007700">() >= </span><span style="color: #0000BB">10 </span><span style="color: #007700">and </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br />});<br /><br /></span><span style="color: #FF8000">// Create stopped timer. It will be inactive until we start it ourselves<br /></span><span style="color: #0000BB">$w_stopped </span><span style="color: #007700">= </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">::</span><span style="color: #0000BB">createStopped</span><span style="color: #007700">(</span><span style="color: #0000BB">10</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">, function(</span><span style="color: #0000BB">$w</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"Callback of a timer created as stopped\n"</span><span style="color: #007700">;<br /><br /> </span><span style="color: #FF8000">// Stop the watcher after 2 iterations<br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">iteration</span><span style="color: #007700">() >= </span><span style="color: #0000BB">2 </span><span style="color: #007700">and </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br />});<br /><br /></span><span style="color: #FF8000">// Loop until Ev::stop() is called or all of watchers stop<br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /><br /></span><span style="color: #FF8000">// Start and look if it works<br /></span><span style="color: #0000BB">$w_stopped</span><span style="color: #007700">-></span><span style="color: #0000BB">start</span><span style="color: #007700">();<br />echo </span><span style="color: #DD0000">"Run single iteration\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">RUN_ONCE</span><span style="color: #007700">);<br /><br />echo </span><span style="color: #DD0000">"Restart the second watcher and try to handle the same events, but don't block\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$w2</span><span style="color: #007700">-></span><span style="color: #0000BB">again</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">RUN_NOWAIT</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">(</span><span style="color: #0000BB">10</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, function() {});<br />echo </span><span style="color: #DD0000">"Running a blocking loop\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br />echo </span><span style="color: #DD0000">"END\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output
something similar to:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
2 seconds elapsed
is called every second, is launched after 2 seconds
iteration = 1
is called every second, is launched after 2 seconds
iteration = 2
is called every second, is launched after 2 seconds
iteration = 3
is called every second, is launched after 2 seconds
iteration = 4
is called every second, is launched after 2 seconds
iteration = 5
Run single iteration
Callback of a timer created as stopped
Restart the second watcher and try to handle the same events, but don't block
Running a blocking loop
is called every second, is launched after 2 seconds
iteration = 8
is called every second, is launched after 2 seconds
iteration = 9
is called every second, is launched after 2 seconds
iteration = 10
END
</pre></div>
</div>
</div>
<div class="example" id="example-3611">
<p><strong>Example #2 Periodic timer. Tick each 10.5 seconds</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvPeriodic</span><span style="color: #007700">(</span><span style="color: #0000BB">0.</span><span style="color: #007700">, </span><span style="color: #0000BB">10.5</span><span style="color: #007700">, </span><span style="color: #0000BB">NULL</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">, </span><span style="color: #0000BB">$revents</span><span style="color: #007700">) {<br /> echo </span><span style="color: #0000BB">time</span><span style="color: #007700">(), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3612">
<p><strong>Example #3 Periodic timer. Use reschedule callback</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Tick each 10.5 seconds<br /><br /></span><span style="color: #007700">function </span><span style="color: #0000BB">reschedule_cb </span><span style="color: #007700">(</span><span style="color: #0000BB">$watcher</span><span style="color: #007700">, </span><span style="color: #0000BB">$now</span><span style="color: #007700">) {<br /> return </span><span style="color: #0000BB">$now </span><span style="color: #007700">+ (</span><span style="color: #0000BB">10.5</span><span style="color: #007700">. - </span><span style="color: #0000BB">fmod</span><span style="color: #007700">(</span><span style="color: #0000BB">$now</span><span style="color: #007700">, </span><span style="color: #0000BB">10.5</span><span style="color: #007700">));<br />}<br /><br /></span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvPeriodic</span><span style="color: #007700">(</span><span style="color: #0000BB">0.</span><span style="color: #007700">, </span><span style="color: #0000BB">0.</span><span style="color: #007700">, </span><span style="color: #DD0000">"reschedule_cb"</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">, </span><span style="color: #0000BB">$revents</span><span style="color: #007700">) {<br /> echo </span><span style="color: #0000BB">time</span><span style="color: #007700">(), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3613">
<p><strong>Example #4 Periodic timer. Tick every 10.5 seconds starting at now</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Tick every 10.5 seconds starting at now<br /></span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvPeriodic</span><span style="color: #007700">(</span><span style="color: #0000BB">fmod</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">now</span><span style="color: #007700">(), </span><span style="color: #0000BB">10.5</span><span style="color: #007700">), </span><span style="color: #0000BB">10.5</span><span style="color: #007700">, </span><span style="color: #0000BB">NULL</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">, </span><span style="color: #0000BB">$revents</span><span style="color: #007700">) {<br /> echo </span><span style="color: #0000BB">time</span><span style="color: #007700">(), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3614">
<p><strong>Example #5 Wait until STDIN is readable</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Wait until STDIN is readable<br /></span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvIo</span><span style="color: #007700">(</span><span style="color: #0000BB">STDIN</span><span style="color: #007700">, </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">READ</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$watcher</span><span style="color: #007700">, </span><span style="color: #0000BB">$revents</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"STDIN is readable\n"</span><span style="color: #007700">;<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">RUN_ONCE</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3615">
<p><strong>Example #6 Use some async I/O to access a socket</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">/* Use some async I/O to access a socket */<br /><br />// `sockets' extension still logs warnings<br />// for EINPROGRESS, EAGAIN/EWOULDBLOCK etc.<br /></span><span style="color: #0000BB">error_reporting</span><span style="color: #007700">(</span><span style="color: #0000BB">E_ERROR</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$e_nonblocking </span><span style="color: #007700">= array (</span><span style="color: #FF8000">/*EAGAIN or EWOULDBLOCK*/</span><span style="color: #0000BB">11</span><span style="color: #007700">, </span><span style="color: #FF8000">/*EINPROGRESS*/</span><span style="color: #0000BB">115</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Get the port for the WWW service<br /></span><span style="color: #0000BB">$service_port </span><span style="color: #007700">= </span><span style="color: #0000BB">getservbyname</span><span style="color: #007700">(</span><span style="color: #DD0000">'www'</span><span style="color: #007700">, </span><span style="color: #DD0000">'tcp'</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Get the IP address for the target host<br /></span><span style="color: #0000BB">$address </span><span style="color: #007700">= </span><span style="color: #0000BB">gethostbyname</span><span style="color: #007700">(</span><span style="color: #DD0000">'google.co.uk'</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Create a TCP/IP socket<br /></span><span style="color: #0000BB">$socket </span><span style="color: #007700">= </span><span style="color: #0000BB">socket_create</span><span style="color: #007700">(</span><span style="color: #0000BB">AF_INET</span><span style="color: #007700">, </span><span style="color: #0000BB">SOCK_STREAM</span><span style="color: #007700">, </span><span style="color: #0000BB">SOL_TCP</span><span style="color: #007700">);<br />if (</span><span style="color: #0000BB">$socket </span><span style="color: #007700">=== </span><span style="color: #0000BB">FALSE</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"socket_create() failed: reason: "<br /> </span><span style="color: #007700">.</span><span style="color: #0000BB">socket_strerror</span><span style="color: #007700">(</span><span style="color: #0000BB">socket_last_error</span><span style="color: #007700">()) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #FF8000">// Set O_NONBLOCK flag<br /></span><span style="color: #0000BB">socket_set_nonblock</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Abort on timeout<br /></span><span style="color: #0000BB">$timeout_watcher </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">(</span><span style="color: #0000BB">10.0</span><span style="color: #007700">, </span><span style="color: #0000BB">0.</span><span style="color: #007700">, function () use (</span><span style="color: #0000BB">$socket</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">socket_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">stop</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">BREAK_ALL</span><span style="color: #007700">);<br />});<br /><br /></span><span style="color: #FF8000">// Make HEAD request when the socket is writable<br /></span><span style="color: #0000BB">$write_watcher </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvIo</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">WRITE</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">)<br /> use (</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">$timeout_watcher</span><span style="color: #007700">, </span><span style="color: #0000BB">$e_nonblocking</span><span style="color: #007700">)<br />{<br /> </span><span style="color: #FF8000">// Stop timeout watcher<br /> </span><span style="color: #0000BB">$timeout_watcher</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /> </span><span style="color: #FF8000">// Stop write watcher<br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /><br /> </span><span style="color: #0000BB">$in </span><span style="color: #007700">= </span><span style="color: #DD0000">"HEAD / HTTP/1.1\r\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$in </span><span style="color: #007700">.= </span><span style="color: #DD0000">"Host: google.co.uk\r\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$in </span><span style="color: #007700">.= </span><span style="color: #DD0000">"Connection: Close\r\n\r\n"</span><span style="color: #007700">;<br /><br /> if (!</span><span style="color: #0000BB">socket_write</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">$in</span><span style="color: #007700">, </span><span style="color: #0000BB">strlen</span><span style="color: #007700">(</span><span style="color: #0000BB">$in</span><span style="color: #007700">))) {<br /> </span><span style="color: #0000BB">trigger_error</span><span style="color: #007700">(</span><span style="color: #DD0000">"Failed writing </span><span style="color: #0000BB">$in</span><span style="color: #DD0000"> to socket"</span><span style="color: #007700">, </span><span style="color: #0000BB">E_USER_ERROR</span><span style="color: #007700">);<br /> }<br /><br /> </span><span style="color: #0000BB">$read_watcher </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvIo</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">READ</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">, </span><span style="color: #0000BB">$re</span><span style="color: #007700">)<br /> use (</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">$e_nonblocking</span><span style="color: #007700">)<br /> {<br /> </span><span style="color: #FF8000">// Socket is readable. recv() 20 bytes using non-blocking mode<br /> </span><span style="color: #0000BB">$ret </span><span style="color: #007700">= </span><span style="color: #0000BB">socket_recv</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">$out</span><span style="color: #007700">, </span><span style="color: #0000BB">20</span><span style="color: #007700">, </span><span style="color: #0000BB">MSG_DONTWAIT</span><span style="color: #007700">);<br /><br /> if (</span><span style="color: #0000BB">$ret</span><span style="color: #007700">) {<br /> echo </span><span style="color: #0000BB">$out</span><span style="color: #007700">;<br /> } elseif (</span><span style="color: #0000BB">$ret </span><span style="color: #007700">=== </span><span style="color: #0000BB">0</span><span style="color: #007700">) {<br /> </span><span style="color: #FF8000">// All read<br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /> </span><span style="color: #0000BB">socket_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">);<br /> return;<br /> }<br /><br /> </span><span style="color: #FF8000">// Caught EINPROGRESS, EAGAIN, or EWOULDBLOCK<br /> </span><span style="color: #007700">if (</span><span style="color: #0000BB">in_array</span><span style="color: #007700">(</span><span style="color: #0000BB">socket_last_error</span><span style="color: #007700">(), </span><span style="color: #0000BB">$e_nonblocking</span><span style="color: #007700">)) {<br /> return;<br /> }<br /><br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /> </span><span style="color: #0000BB">socket_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">);<br /> });<br /><br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br />});<br /><br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">socket_connect</span><span style="color: #007700">(</span><span style="color: #0000BB">$socket</span><span style="color: #007700">, </span><span style="color: #0000BB">$address</span><span style="color: #007700">, </span><span style="color: #0000BB">$service_port</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output
something similar to:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
HTTP/1.1 301 Moved Permanently
Location: http://www.google.co.uk/
Content-Type: text/html; charset=UTF-8
Date: Sun, 23 Dec 2012 16:08:27 GMT
Expires: Tue, 22 Jan 2013 16:08:27 GMT
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 221
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Connection: close
</pre></div>
</div>
</div>
<div class="example" id="example-3616">
<p><strong>Example #7 Embedding one loop into another</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">/*<br />* Try to get an embeddable event loop and embed it into the default event loop.<br />* If it is impossible, use the default<br />* loop. The default loop is stored in $loop_hi, while the embeddable loop is<br />* stored in $loop_lo(which is $loop_hi in the case no embeddable loop can be<br />* used).<br />*<br />* Sample translated to PHP<br />* http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#Examples_CONTENT-9<br />*/<br /></span><span style="color: #0000BB">$loop_hi </span><span style="color: #007700">= </span><span style="color: #0000BB">EvLoop</span><span style="color: #007700">::</span><span style="color: #0000BB">defaultLoop</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$loop_lo </span><span style="color: #007700">= </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$embed </span><span style="color: #007700">= </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">/*<br />* See if there is a chance of getting one that works<br />* (flags' value of 0 means autodetection)<br />*/<br /></span><span style="color: #0000BB">$loop_lo </span><span style="color: #007700">= </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">embeddableBackends</span><span style="color: #007700">() & </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">recommendedBackends</span><span style="color: #007700">()<br /> ? new </span><span style="color: #0000BB">EvLoop</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">embeddableBackends</span><span style="color: #007700">() & </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">recommendedBackends</span><span style="color: #007700">())<br /> : </span><span style="color: #0000BB">0</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">$loop_lo</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$embed </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvEmbed</span><span style="color: #007700">(</span><span style="color: #0000BB">$loop_lo</span><span style="color: #007700">, function () {});<br />} else {<br /> </span><span style="color: #0000BB">$loop_lo </span><span style="color: #007700">= </span><span style="color: #0000BB">$loop_hi</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3617">
<p><strong>Example #8 Embedding loop created with kqueue backend into the default loop</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">/*<br />* Check if kqueue is available but not recommended and create a kqueue backend<br />* for use with sockets (which usually work with any kqueue implementation).<br />* Store the kqueue/socket-only event loop in loop_socket. (One might optionally<br />* use EVFLAG_NOENV, too)<br />*<br />* Example borrowed from<br />* http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#Examples_CONTENT-9<br />*/<br /></span><span style="color: #0000BB">$loop </span><span style="color: #007700">= </span><span style="color: #0000BB">EvLoop</span><span style="color: #007700">::</span><span style="color: #0000BB">defaultLoop</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$socket_loop </span><span style="color: #007700">= </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$embed </span><span style="color: #007700">= </span><span style="color: #0000BB">NULL</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">supportedBackends</span><span style="color: #007700">() & ~</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">recommendedBackends</span><span style="color: #007700">() & </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">BACKEND_KQUEUE</span><span style="color: #007700">) {<br /> if ((</span><span style="color: #0000BB">$socket_loop </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvLoop</span><span style="color: #007700">(</span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">BACKEND_KQUEUE</span><span style="color: #007700">))) {<br /> </span><span style="color: #0000BB">$embed </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvEmbed</span><span style="color: #007700">(</span><span style="color: #0000BB">$loop</span><span style="color: #007700">);<br /> }<br />}<br /><br />if (!</span><span style="color: #0000BB">$socket_loop</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$socket_loop </span><span style="color: #007700">= </span><span style="color: #0000BB">$loop</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #FF8000">// Now use $socket_loop for all sockets, and $loop for anything else<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3618">
<p><strong>Example #9 Handle SIGTERM signal</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvSignal</span><span style="color: #007700">(</span><span style="color: #0000BB">SIGTERM</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$watcher</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"SIGTERM received\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$watcher</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3619">
<p><strong>Example #10 Monitor changes of /var/log/messages</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Use 10 second update interval.<br /></span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvStat</span><span style="color: #007700">(</span><span style="color: #DD0000">"/var/log/messages"</span><span style="color: #007700">, </span><span style="color: #0000BB">8</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"/var/log/messages changed\n"</span><span style="color: #007700">;<br /><br /> </span><span style="color: #0000BB">$attr </span><span style="color: #007700">= </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">attr</span><span style="color: #007700">();<br /><br /> if (</span><span style="color: #0000BB">$attr</span><span style="color: #007700">[</span><span style="color: #DD0000">'nlink'</span><span style="color: #007700">]) {<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Current size: %ld\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$attr</span><span style="color: #007700">[</span><span style="color: #DD0000">'size'</span><span style="color: #007700">]);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Current atime: %ld\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$attr</span><span style="color: #007700">[</span><span style="color: #DD0000">'atime'</span><span style="color: #007700">]);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Current mtime: %ld\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$attr</span><span style="color: #007700">[</span><span style="color: #DD0000">'mtime'</span><span style="color: #007700">]);<br /> } else {<br /> </span><span style="color: #0000BB">fprintf</span><span style="color: #007700">(</span><span style="color: #0000BB">STDERR</span><span style="color: #007700">, </span><span style="color: #DD0000">"`messages` file is not there!"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /> }<br />});<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3620">
<p><strong>Example #11 Monotor changes of /var/log/messages. Avoid missing updates by means of one second delay</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$timer </span><span style="color: #007700">= </span><span style="color: #0000BB">EvTimer</span><span style="color: #007700">::</span><span style="color: #0000BB">createStopped</span><span style="color: #007700">(</span><span style="color: #0000BB">0.</span><span style="color: #007700">, </span><span style="color: #0000BB">1.02</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /><br /> </span><span style="color: #0000BB">$stat </span><span style="color: #007700">= </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">data</span><span style="color: #007700">;<br /><br /> </span><span style="color: #FF8000">// 1 second after the most recent change of the file<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Current size: %ld\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$stat</span><span style="color: #007700">-></span><span style="color: #0000BB">attr</span><span style="color: #007700">()[</span><span style="color: #DD0000">'size'</span><span style="color: #007700">]);<br />});<br /><br /></span><span style="color: #0000BB">$stat </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvStat</span><span style="color: #007700">(</span><span style="color: #DD0000">"/var/log/messages"</span><span style="color: #007700">, </span><span style="color: #0000BB">0.</span><span style="color: #007700">, function () use (</span><span style="color: #0000BB">$timer</span><span style="color: #007700">) {<br /> </span><span style="color: #FF8000">// Reset timer watcher<br /> </span><span style="color: #0000BB">$timer</span><span style="color: #007700">-></span><span style="color: #0000BB">again</span><span style="color: #007700">();<br />});<br /><br /></span><span style="color: #0000BB">$timer</span><span style="color: #007700">-></span><span style="color: #0000BB">data </span><span style="color: #007700">= </span><span style="color: #0000BB">$stat</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
<div class="example" id="example-3621">
<p><strong>Example #12 Process status changes</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$pid </span><span style="color: #007700">= </span><span style="color: #0000BB">pcntl_fork</span><span style="color: #007700">();<br /><br />if (</span><span style="color: #0000BB">$pid </span><span style="color: #007700">== -</span><span style="color: #0000BB">1</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">fprintf</span><span style="color: #007700">(</span><span style="color: #0000BB">STDERR</span><span style="color: #007700">, </span><span style="color: #DD0000">"pcntl_fork failed\n"</span><span style="color: #007700">);<br />} elseif (</span><span style="color: #0000BB">$pid</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$w </span><span style="color: #007700">= new </span><span style="color: #0000BB">EvChild</span><span style="color: #007700">(</span><span style="color: #0000BB">$pid</span><span style="color: #007700">, </span><span style="color: #0000BB">FALSE</span><span style="color: #007700">, function (</span><span style="color: #0000BB">$w</span><span style="color: #007700">, </span><span style="color: #0000BB">$revents</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">stop</span><span style="color: #007700">();<br /><br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Process %d exited with status %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">rpid</span><span style="color: #007700">, </span><span style="color: #0000BB">$w</span><span style="color: #007700">-></span><span style="color: #0000BB">rstatus</span><span style="color: #007700">);<br /> });<br /><br /> </span><span style="color: #0000BB">Ev</span><span style="color: #007700">::</span><span style="color: #0000BB">run</span><span style="color: #007700">();<br /><br /> </span><span style="color: #FF8000">// Protect against Zombies<br /> </span><span style="color: #0000BB">pcntl_wait</span><span style="color: #007700">(</span><span style="color: #0000BB">$status</span><span style="color: #007700">);<br />} else {<br /> </span><span style="color: #FF8000">//Forked child<br /> </span><span style="color: #007700">exit(</span><span style="color: #0000BB">2</span><span style="color: #007700">);<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</div>
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