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?>
<div id="function.gzseek" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">gzseek</h1>
  <p class="verinfo">(PHP 4, PHP 5, PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">gzseek</span> &mdash; <span class="dc-title">Seek on a gz-file pointer</span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.gzseek-description">
  <h3 class="title">Descrizione</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>gzseek</strong></span>(<span class="methodparam"><span class="type"><a href="language.types.resource.php" class="type resource">resource</a></span> <code class="parameter">$stream</code></span>, <span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$offset</code></span>, <span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$whence</code><span class="initializer"> = <strong><code><a href="filesystem.constants.php#constant.seek-set">SEEK_SET</a></code></strong></span></span>): <span class="type"><a href="language.types.integer.php" class="type int">int</a></span></div>

  <p class="para rdfs-comment">
   Sets the file position indicator for the given file pointer to the
   given offset byte into the file stream. Equivalent to calling (in C)
   <code class="literal">gzseek(zp, offset, SEEK_SET)</code>.
  </p>
  <p class="para">
   If the file is opened for reading, this function is emulated but
   can be extremely slow. If the file is opened for writing, only
   forward seeks are supported; <span class="function"><strong>gzseek()</strong></span> then compresses
   a sequence of zeroes up to the new starting position.
  </p>
 </div>

 <div class="refsect1 parameters" id="refsect1-function.gzseek-parameters">
  <h3 class="title">Elenco dei parametri</h3>
  <p class="para">
   <dl>
    
     <dt><code class="parameter">stream</code></dt>
     <dd>
      <p class="para">
       The gz-file pointer. It must be valid, and must point to a file
       successfully opened by <span class="function"><a href="function.gzopen.php" class="function">gzopen()</a></span>.
      </p>
     </dd>
    
    
     <dt><code class="parameter">offset</code></dt>
     <dd>
      <p class="para">
       The seeked offset.
      </p>
     </dd>
    
    
     <dt><code class="parameter">whence</code></dt>
     <dd>
      <p class="para">
       <code class="parameter">whence</code> values are:
       <ul class="simplelist">
        <li><strong><code><a href="filesystem.constants.php#constant.seek-set">SEEK_SET</a></code></strong> - Set position equal to <code class="parameter">offset</code> bytes.</li>
        <li><strong><code><a href="filesystem.constants.php#constant.seek-cur">SEEK_CUR</a></code></strong> - Set position to current location plus <code class="parameter">offset</code>.</li>
       </ul>
      </p>
      <p class="para">
       If <code class="parameter">whence</code> is not specified, it is assumed to be
       <strong><code><a href="filesystem.constants.php#constant.seek-set">SEEK_SET</a></code></strong>.
      </p>
     </dd>
    
   </dl>
  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.gzseek-returnvalues">
  <h3 class="title">Valori restituiti</h3>
  <p class="para">
   Upon success, returns 0; otherwise, returns -1. Note that seeking
   past EOF is not considered an error.
  </p>
 </div>

 <div class="refsect1 examples" id="refsect1-function.gzseek-examples">
  <h3 class="title">Esempi</h3>
  <p class="para">
   <div class="example" id="example-1">
    <p><strong>Example #1 <span class="function"><strong>gzseek()</strong></span> example</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br />$gz </span><span style="color: #007700">= </span><span style="color: #0000BB">gzopen</span><span style="color: #007700">(</span><span style="color: #DD0000">'somefile.gz'</span><span style="color: #007700">, </span><span style="color: #DD0000">'r'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">gzseek</span><span style="color: #007700">(</span><span style="color: #0000BB">$gz</span><span style="color: #007700">,</span><span style="color: #0000BB">2</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">gzgetc</span><span style="color: #007700">(</span><span style="color: #0000BB">$gz</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">gzclose</span><span style="color: #007700">(</span><span style="color: #0000BB">$gz</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>
    </div>

   </div>
  </p>
 </div>

 <div class="refsect1 seealso" id="refsect1-function.gzseek-seealso">
  <h3 class="title">Vedere anche:</h3>
  <p class="para">
   <ul class="simplelist">
    <li><span class="function"><a href="function.gztell.php" class="function" rel="rdfs-seeAlso">gztell()</a> - Tell gz-file pointer read/write position</span></li>
    <li><span class="function"><a href="function.gzrewind.php" class="function" rel="rdfs-seeAlso">gzrewind()</a> - Rewind the position of a gz-file pointer</span></li>
   </ul>
  </p>
 </div>

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