65 lines
4.8 KiB
HTML
65 lines
4.8 KiB
HTML
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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html
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PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html lang="en-us" xml:lang="en-us">
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<head>
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<meta name="DC.Title" content="One-time initialization and thread safety" />
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<meta name="abstract" content="At times, you might want to defer the initialization of resources until a thread requires them. However, your application might require that multiple threads use a certain resource, which requires you to initialize the resource only once in a threadsafe way." />
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<meta name="description" content="At times, you might want to defer the initialization of resources until a thread requires them. However, your application might require that multiple threads use a certain resource, which requires you to initialize the resource only once in a threadsafe way." />
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<meta name="DC.Relation" scheme="URI" content="rzahwmulco.htm" />
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<meta name="DC.Relation" scheme="URI" content="rzahwe15rx.htm" />
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<meta name="DC.Relation" scheme="URI" content="rzahwe16rx.htm" />
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<meta name="DC.Relation" scheme="URI" content="rzahwdatco.htm" />
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<meta name="DC.Relation" scheme="URI" content="rzahwnonco.htm" />
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<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
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<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
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<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
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<link rel="stylesheet" type="text/css" href="./ic.css" />
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<title>One-time initialization and thread safety</title>
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</head>
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<body id="rzahwone-oneco"><a name="rzahwone-oneco"><!-- --></a>
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<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
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<h1 class="topictitle1">One-time initialization and thread safety</h1>
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<div><p>At times, you might want to defer the initialization of resources
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until a thread requires them. However, your application might require that
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multiple threads use a certain resource, which requires you to initialize
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the resource only once in a threadsafe way.</p>
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<p>There are several ways you can initialize a resource that is used multiple
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times in a threadsafe fashion. Most of these methods involve a Boolean
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value to allow the application to quickly determine whether the required initialization
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is completed. You must also use a synchronization technique in addition to
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the Boolean flag to ensure that the initialization completed.</p>
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</div>
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<div>
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<ul class="ullinks">
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<li class="ulchildlink"><strong><a href="rzahwe15rx.htm">Example: One-time initialization in Pthread programs</a></strong><br />
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This example shows a Pthread program that is dynamically initializing an integer using the Pthread one time initialization support.</li>
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</ul>
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<div class="familylinks">
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<div class="parentlink"><strong>Parent topic:</strong> <a href="rzahwmulco.htm" title="If you are going to write multithreaded applications or server applications for i5/OS, you should be familiar with several techniques.">Multithreaded programming techniques</a></div>
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</div>
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<div class="relconcepts"><strong>Related concepts</strong><br />
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<div><a href="rzahwnonco.htm" title="Your multithreaded application at times requires access to functions or system services that are not thread safe. There are few completely safe alternatives for calling these functions.">Function calls that are not thread safe</a></div>
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<div><a href="rzahwcomco.htm" title="Several programming errors often occur when writing multithreaded applications.">Common multithreaded programming errors</a></div>
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</div>
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<div class="relref"><strong>Related reference</strong><br />
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<div><a href="rzahwe16rx.htm" title="This example shows a Pthread program that is dynamically initializing an integer using the space location lock synchronization primitive.">Example: Space location locks in Pthread programs</a></div>
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<div><a href="rzahwdatco.htm" title="Typical applications that are not threaded use global storage.">Thread-specific data</a></div>
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</div>
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</div>
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</body>
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</html>
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