<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Predefined Constants</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="hash.resources.html">Resource Types</a></div> <div class="next" style="text-align: right; float: right;"><a href="ref.hash.html">Hash Functions</a></div> <div class="up"><a href="book.hash.html">Hash</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="hash.constants" class="appendix"> <h1>Predefined Constants</h1> <p class="simpara"> The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime. </p> <dl> <dt id="constant.hash-hmac"> <span class="term"> <strong><code>HASH_HMAC</code></strong> (<span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span>) </span> <dd> <span class="simpara"> Optional flag for <span class="function"><a href="function.hash-init.html" class="function">hash_init()</a></span>. Indicates that the HMAC digest-keying algorithm should be applied to the current hashing context. </span> </dd> </dt> </dl> </div> <hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="hash.resources.html">Resource Types</a></div> <div class="next" style="text-align: right; float: right;"><a href="ref.hash.html">Hash Functions</a></div> <div class="up"><a href="book.hash.html">Hash</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>