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<title>Truncates a file to a given length</title>
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</div><hr /><div id="function.ftruncate" class="refentry">
<div class="refnamediv">
<h1 class="refname">ftruncate</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">ftruncate</span> — <span class="dc-title">Truncates a file to a given length</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.ftruncate-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>ftruncate</strong></span>
( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$handle</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$size</code></span>
)</div>
<p class="para rdfs-comment">
Takes the filepointer, <em><code class="parameter">handle</code></em>, and truncates the file to
length, <em><code class="parameter">size</code></em>.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.ftruncate-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">handle</code></em></span>
<dd>
<p class="para">
The file pointer.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
The <em><code class="parameter">handle</code></em> must be open for writing.
</p>
</p></blockquote>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">size</code></em></span>
<dd>
<p class="para">
The size to truncate to.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
If <em><code class="parameter">size</code></em> is larger than the file then the file
is extended with null bytes.
</p>
<p class="para">
If <em><code class="parameter">size</code></em> is smaller than the file then the file
is truncated to that size.
</p>
</p></blockquote>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.ftruncate-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.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.ftruncate-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>4.3.3</td>
<td>
Prior to this release <span class="function"><strong>ftruncate()</strong></span> returned an
<span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span> value of 1 on success, instead of
<span class="type"><a href="language.types.boolean.html" class="type boolean">boolean</a></span> <strong><code>TRUE</code></strong>.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.ftruncate-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-2396">
<p><strong>Example #1 File truncation example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$filename </span><span style="color: #007700">= </span><span style="color: #DD0000">'lorem_ipsum.txt'</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$handle </span><span style="color: #007700">= </span><span style="color: #0000BB">fopen</span><span style="color: #007700">(</span><span style="color: #0000BB">$filename</span><span style="color: #007700">, </span><span style="color: #DD0000">'r+'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">ftruncate</span><span style="color: #007700">(</span><span style="color: #0000BB">$handle</span><span style="color: #007700">, </span><span style="color: #0000BB">rand</span><span style="color: #007700">(</span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">filesize</span><span style="color: #007700">(</span><span style="color: #0000BB">$filename</span><span style="color: #007700">)));<br /></span><span style="color: #0000BB">rewind</span><span style="color: #007700">(</span><span style="color: #0000BB">$handle</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">fread</span><span style="color: #007700">(</span><span style="color: #0000BB">$handle</span><span style="color: #007700">, </span><span style="color: #0000BB">filesize</span><span style="color: #007700">(</span><span style="color: #0000BB">$filename</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">fclose</span><span style="color: #007700">(</span><span style="color: #0000BB">$handle</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.ftruncate-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
The file pointer is <em class="emphasis">not</em> changed.
</p>
</p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.ftruncate-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.fopen.html" class="function" rel="rdfs-seeAlso">fopen()</a> - Opens file or URL</span></li>
<li class="member"> <span class="function"><a href="function.fseek.html" class="function" rel="rdfs-seeAlso">fseek()</a> - Seeks on a file pointer</span></li>
</ul>
</p>
</div>
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