<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation"> <title>Using User Queue APIs</title> <!-- All rights reserved. Licensed Materials Property of IBM --> <!-- US Government Users Restricted Rights --> <!-- Use, duplication or disclosure restricted by --> <!-- GSA ADP Schedule Contract with IBM Corp. --> <!-- Change History: --> <!-- YYMMDD USERID Change description --> <!-- End Header Records --> <link rel="stylesheet" type="text/css" href="../rzahg/ic.css"> </head> <body> <!-- Java sync-link --> <script type="text/javascript" language="Javascript" src="../rzahg/synch.js"> </script> <a name="Top_Of_Page"></a> <h2>Using User Queue APIs</h2> <p>You can use user queues to:</p> <ul> <li>Communicate between two processes asynchronously.</li> <li>Store data in arrival sequence for later use.</li> <li>Contain keyed messages.</li> <li>Create a batch machine. (For an example, see <a href="../apiref/apiexcremac.htm">Creating a Batch Machine</a> in API Examples.)</li> <li>Permit better performance than the data queue interface.</li> </ul> <p>You can save and restore a user queue; however, you can save or restore its definition only. You cannot save or restore the messages in it. You cannot restore a user queue if a user queue with the same name already exists in the library. You must provide programs to use this object type to enqueue and dequeue messages.</p> <p> In addition to the user queue APIs, you can work with user queues through the following:</p> <ul> <li>ILE C programming language</li> <li>Delete User Queue (DLTUSRQ) command</li> <li>Machine interface (MI) instructions</li> </ul> <p>For details about MI instructions, refer to the <a href="../rzatk/mitoc.htm">iSeries Machine Interface Instructions</a>, which provides detailed descriptions of the iSeries<SUP>(TM)</SUP> machine interface instruction fields and the formats of those fields. For details about the DLTUSRQ command, see the <a href="../rbam6/rbam6clmain.htm">Control Language</a> topic.</p> <br> <hr> <center> <table cellpadding="2" cellspacing="2"> <tr align="center"> <td valign="middle" align="center"> <a href="obj1.htm">Object APIs</a> | <a href="aplist.htm">APIs by category</a></td> </tr> </table> </center> </body> </html>