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<refentry xml:id="function.hash" xmlns="http://docbook.org/ns/docbook">
 <refnamediv>
  <refname>hash</refname>
  <refpurpose>Generate a hash value (message digest)</refpurpose>
 </refnamediv>
 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <type>string</type><methodname>hash</methodname>
   <methodparam><type>string</type><parameter>algo</parameter></methodparam>
   <methodparam><type>string</type><parameter>data</parameter></methodparam>
   <methodparam choice="opt"><type>bool</type><parameter>binary</parameter><initializer>&false;</initializer></methodparam>
   <methodparam choice="opt"><type>array</type><parameter>options</parameter><initializer>[]</initializer></methodparam>
  </methodsynopsis>

 </refsect1>
 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term><parameter>algo</parameter></term>
     <listitem>
      <para>
       Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..). For a list of supported algorithms see <function>hash_algos</function>.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>data</parameter></term>
     <listitem>
      <para>
       Message to be hashed.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>binary</parameter></term>
     <listitem>
      <para>
       When set to &true;, outputs raw binary data.
       &false; outputs lowercase hexits.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>options</parameter></term>
     <listitem>
      <para>
       An array of options for the various hashing algorithms.  Currently, only the "seed" parameter is
       supported by the MurmurHash variants.
      </para>
     </listitem>
    </varlistentry>
   </variablelist>
  </para>
 </refsect1>

 <refsect1 role="returnvalues">
  &reftitle.returnvalues;
  <para>
   Returns a string containing the calculated message digest as lowercase hexits
   unless <parameter>binary</parameter> is set to true in which case the raw
   binary representation of the message digest is returned.
  </para>
 </refsect1>

 <refsect1 role="changelog">
  &reftitle.changelog;
  <para>
   <informaltable>
    <tgroup cols="2">
     <thead>
      <row>
       <entry>&Version;</entry>
       <entry>&Description;</entry>
      </row>
     </thead>
     <tbody>
      <row>
       <entry>8.1.0</entry>
       <entry>The <parameter>options</parameter> parameter has been added.</entry>
      </row>
      <row>
       <entry>8.0.0</entry>
       <entry>
        <function>hash</function> now throws a <classname>ValueError</classname> exception
        if <parameter>algo</parameter> is unknown; previously, &false; was returned instead.
       </entry>
      </row>
     </tbody>
    </tgroup>
   </informaltable>
  </para>
 </refsect1>

 <refsect1 role="examples">
  &reftitle.examples;
  <para>
   <example>
    <title>A <function>hash</function> example</title>
    <programlisting role="php">
<![CDATA[
<?php
echo hash('sha256', 'The quick brown fox jumped over the lazy dog.');
?>
]]>
    </programlisting>
    &example.outputs;
    <screen>
<![CDATA[
68b1282b91de2c054c36629cb8dd447f12f096d3e3c587978dc2248444633483
]]>
    </screen>
   </example>
  </para>
 </refsect1>

 <refsect1 role="seealso">
  &reftitle.seealso;
  <para>
   <simplelist>
    <member><function>hash_file</function></member>
    <member><function>hash_hmac</function></member>
    <member><function>hash_init</function></member>
    <member><function>md5</function></member>
    <member><function>sha1</function></member>
   </simplelist>
  </para>
 </refsect1>

</refentry>
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