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<div class="refnamediv">
<h1 class="refname">debug_print_backtrace</h1>
<p class="verinfo">(PHP 5)</p><p class="refpurpose"><span class="refname">debug_print_backtrace</span> — <span class="dc-title">
Prints a backtrace
</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.debug-print-backtrace-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type"><span class="type void">void</span></span> <span class="methodname"><strong>debug_print_backtrace</strong></span>
([ <span class="methodparam"><span class="type">int</span> <code class="parameter">$options</code><span class="initializer"> = 0</span></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$limit</code><span class="initializer"> = 0</span></span>
]] )</div>
<p class="para rdfs-comment">
<span class="function"><strong>debug_print_backtrace()</strong></span> prints a PHP backtrace. It
prints the function calls, included/required files and
<span class="function"><a href="function.eval.html" class="function">eval()</a></span>ed stuff.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.debug-print-backtrace-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">options</code></em></span>
<dd>
<p class="para">
As of 5.3.6, this parameter is a bitmask for the following options:
<table class="doctable table">
<caption><strong> <span class="function"><strong>debug_print_backtrace()</strong></span> options</strong></caption>
<tbody class="tbody">
<tr>
<td>DEBUG_BACKTRACE_IGNORE_ARGS</td>
<td>
Whether or not to omit the "args" index, and thus all the function/method arguments,
to save memory.
</td>
</tr>
</tbody>
</table>
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">limit</code></em></span>
<dd>
<p class="para">
As of 5.4.0, this parameter can be used to limit the number of stack frames printed.
By default (<em><code class="parameter">limit</code></em>=<em>0</em>) it prints all stack frames.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.debug-print-backtrace-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
No value is returned.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.debug-print-backtrace-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>5.4.0</td>
<td>
Added the optional parameter <em><code class="parameter">limit</code></em>.
</td>
</tr>
<tr>
<td>5.3.6</td>
<td>
Added the optional parameter <em><code class="parameter">options</code></em>.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.debug-print-backtrace-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-450">
<p><strong>Example #1 <span class="function"><strong>debug_print_backtrace()</strong></span> example</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">// include.php file<br /><br /></span><span style="color: #007700">function </span><span style="color: #0000BB">a</span><span style="color: #007700">() {<br /> </span><span style="color: #0000BB">b</span><span style="color: #007700">();<br />}<br /><br />function </span><span style="color: #0000BB">b</span><span style="color: #007700">() {<br /> </span><span style="color: #0000BB">c</span><span style="color: #007700">();<br />}<br /><br />function </span><span style="color: #0000BB">c</span><span style="color: #007700">(){<br /> </span><span style="color: #0000BB">debug_print_backtrace</span><span style="color: #007700">();<br />}<br /><br /></span><span style="color: #0000BB">a</span><span style="color: #007700">();<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// test.php file<br />// this is the file you should run<br /><br /></span><span style="color: #007700">include </span><span style="color: #DD0000">'include.php'</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>
#0 c() called at [/tmp/include.php:10]
#1 b() called at [/tmp/include.php:6]
#2 a() called at [/tmp/include.php:17]
#3 include(/tmp/include.php) called at [/tmp/test.php:3]
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.debug-print-backtrace-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.debug-backtrace.html" class="function" rel="rdfs-seeAlso">debug_backtrace()</a> - Generates a backtrace</span></li>
</ul>
</p>
</div>
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