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<div class="refnamediv">
<h1 class="refname">proc_nice</h1>
<p class="verinfo">(PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">proc_nice</span> — <span class="dc-title">Change the priority of the current process</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.proc-nice-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>proc_nice</strong></span>
( <span class="methodparam"><span class="type">int</span> <code class="parameter">$increment</code></span>
)</div>
<p class="para rdfs-comment">
<span class="function"><strong>proc_nice()</strong></span> changes the priority of the current
process by the amount specified in <code class="parameter">increment</code>. A
positive <code class="parameter">increment</code> will lower the priority of the
current process, whereas a negative <code class="parameter">increment</code>
will raise the priority.
</p>
<p class="para">
<span class="function"><strong>proc_nice()</strong></span> is not related to
<span class="function"><a href="function.proc-open.html" class="function">proc_open()</a></span> and its associated functions in any way.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.proc-nice-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">increment</code></dt>
<dd>
<p class="para">
The new priority value, the value of this may differ on platforms.
</p>
<p class="para">
On Unix, a low value, such as <em>-20</em> means high priority
wheras a positive value have a lower priority.
</p>
<p class="para">
For Windows the <code class="parameter">increment</code> parameter have the
following meanings:
</p>
<table class="doctable informaltable">
<thead>
<tr>
<th>Priority class</th>
<th>Possible values</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td style="vertical-align: top;">High priority</td>
<td style="vertical-align: top;">
<code class="parameter">increment</code> <em>< -9</em>
</td>
</tr>
<tr>
<td style="vertical-align: top;">Above normal priority</td>
<td style="vertical-align: top;">
<code class="parameter">increment</code> <em>< -4</em>
</td>
</tr>
<tr>
<td style="vertical-align: top;">Normal priority</td>
<td style="vertical-align: top;">
<code class="parameter">increment</code> <em>< 5</em> &
<code class="parameter">increment</code> <em>> -5</em>
</td>
</tr>
<tr>
<td style="vertical-align: top;">Below normal priority</td>
<td style="vertical-align: top;">
<code class="parameter">increment</code> <em>> 5</em>
</td>
</tr>
<tr>
<td style="vertical-align: top;">Idle priority</td>
<td style="vertical-align: top;">
<code class="parameter">increment</code> <em>> 9</em>
</td>
</tr>
</tbody>
</table>
</dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.proc-nice-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> on success or <strong><code>FALSE</code></strong> on failure.
If an error occurs, like the user lacks permission to change the priority,
an error of level <strong><code>E_WARNING</code></strong> is also generated.
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.proc-nice-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-4489">
<p><strong>Example #1 Using <span class="function"><strong>proc_nice()</strong></span> to set the process priority to high</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">// Highest priority<br /></span><span style="color: #0000BB">proc_nice</span><span style="color: #007700">(-</span><span style="color: #0000BB">20</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.proc-nice-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>7.2.0</td>
<td>
This function is now available on Windows.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.proc-nice-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<strong>Availability</strong><br />
<p class="para">
<span class="function"><strong>proc_nice()</strong></span> will only exist if your system has 'nice'
capabilities. 'nice' conforms to: SVr4, SVID EXT, AT&T, X/OPEN, BSD
4.3.
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<strong>Windows only</strong><br />
<p class="para">
<span class="function"><strong>proc_nice()</strong></span> will change the <em class="emphasis">current</em> process
priority, even if PHP was compiled using thread safety.
</p>
</p></blockquote>
</div>
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