archived-doc-en/reference/misc/functions/exit.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xml:id="function.exit" xmlns="http://docbook.org/ns/docbook">
 <refnamediv>
  <refname>exit</refname>
  <refpurpose>Output a message and terminate the current script</refpurpose>
 </refnamediv>
 
 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <type>void</type><methodname>exit</methodname>
   <methodparam choice="opt"><type>string</type><parameter>status</parameter></methodparam>
  </methodsynopsis>
  <methodsynopsis>
   <type>void</type><methodname>exit</methodname>
   <methodparam><type>int</type><parameter>status</parameter></methodparam>
  </methodsynopsis>
  <para>
   Terminates execution of the script.
   <link linkend="function.register-shutdown-function">Shutdown functions</link>
   and <link linkend="language.oop5.decon.destructor">object destructors</link>
   will always be executed even if <literal>exit</literal> is called.
  </para>
  <para>
   <literal>exit</literal> is a language construct and it can be called
   without parentheses if no <parameter>status</parameter> is passed.
  </para>
 </refsect1>

 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term><parameter>status</parameter></term>
     <listitem>
      <para>
       If <parameter>status</parameter> is a string, this function prints the
       <parameter>status</parameter> just before exiting.
      </para>
      <para>
       If <parameter>status</parameter> is an <type>integer</type>, that
       value will be used as the exit status and not printed. Exit statuses should be in
       the range 0 to 254, the exit status 255 is reserved by PHP and shall
       not be used. The status 0 is used to terminate the program
       successfully.
      </para>
      <note>
       <simpara>
        PHP &gt;= 4.2.0 does NOT print the <parameter>status</parameter>
        if it is an <type>integer</type>.
       </simpara>
      </note>
     </listitem>
    </varlistentry>
   </variablelist>
  </para>
 </refsect1>

 <refsect1 role="returnvalues">
  &reftitle.returnvalues;
  <para>
   &return.void;
  </para>
 </refsect1>

 <refsect1 role="examples">
  &reftitle.examples;
  <para>
   <example>
    <title><literal>exit</literal> example</title>
    <programlisting role="php">
<![CDATA[
<?php

$filename = '/path/to/data-file';
$file = fopen($filename, 'r')
    or exit("unable to open file ($filename)");

?>
]]>
    </programlisting>
   </example>
  </para>
  <para>
   <example>
    <title><literal>exit</literal> status example</title>
    <programlisting role="php">
<![CDATA[
<?php

//exit program normally
exit;
exit();
exit(0);

//exit with an error code
exit(1);
exit(0376); //octal

?>
]]>
    </programlisting>
   </example>
  </para>
  <para>
   <example>
    <title>Shutdown functions and destructors run regardless</title>
    <programlisting role="php">
<![CDATA[
<?php
class Foo
{
    public function __destruct()
    {
        echo 'Destruct: ' . __METHOD__ . '()' . PHP_EOL;
    }
}

function shutdown()
{
    echo 'Shutdown: ' . __FUNCTION__ . '()' . PHP_EOL;
}

$foo = new Foo();
register_shutdown_function('shutdown');

exit();
echo 'This will not be output.';
?>
]]>
    </programlisting>
    &example.outputs;
    <screen>
 <![CDATA[
 Shutdown: shutdown()
 Destruct: Foo::__destruct()
 ]]>
    </screen>
   </example>
  </para>
 </refsect1>

 <refsect1 role="notes">
  &reftitle.notes;
  
  &note.language-construct;

  <note>
   <para>
    This language construct is equivalent to <link linkend="function.die"><literal>die</literal></link>.
   </para>
  </note>
 </refsect1>

 <refsect1 role="seealso">
  &reftitle.seealso;
  <para>
   <simplelist>
    <member><function>register_shutdown_function</function></member>
   </simplelist>
  </para>
 </refsect1>

</refentry>

<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->