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<concept id="GUID-1D6DD213-1EEC-58D2-8311-7A1AF77960C1" xml:lang="en"><title>How

to issue requests</title><shortdesc>This document describes how an active object issues a request for

a service.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>Once the active object has been constructed, a request can be issued. In

the following code fragment, the active object provides the function <codeph>IssueRequest()</codeph> to

invoke the encapsulated service function.</p>

<codeblock id="GUID-9C89E661-AD2E-520A-8E8D-F6D4E667706A" xml:space="preserve">void CExampleActiveObject::IssueRequest()

    {

        // Request the service

    iServiceProvider-> RequestTheService(iStatus);

        // Indicate request has been issued

    SetActive();

    }</codeblock>

<ul>

<li id="GUID-8359DED4-C349-51AF-8771-111716DC49B3"><p>Pass the <codeph>TRequestStatus</codeph> object,

provided by the active objects's <codeph>CActive</codeph> base class, to the

service function. As part of its processing, the service function sets this

to <codeph>KRequestPending</codeph>, indicating that the request has been

issued but is not yet complete.</p> </li>

<li id="GUID-E3652D72-749D-577D-8ED3-9FCEDCB2CCA9"><p>Set the base class's

active request flag, using the function <codeph>SetActive()</codeph>, to indicate

that the active object is currently active. The flag is reset by the active

scheduler before handling a completed request, or by the active object base

class as part of the cancellation protocol.</p> </li>

</ul>

<section id="GUID-213A1B18-AD81-478A-BC14-F8030F9AF095"><title>Completing a request</title> <p>At some point, the service

provider's processing completes and it calls <codeph>RThread::RequestComplete()</codeph> passing

the request status object and the service provider's return code, a value

other than <codeph>KRequestPending</codeph>. This results in the active object's <codeph>iStatus</codeph> member

being set to the return code value and a signal that the request is complete.</p> </section>