Symbian3/SDK/Source/GUID-092C18D4-A525-5562-9BF6-41435E400290.dita
author Dominic Pinkman <dominic.pinkman@nokia.com>
Tue, 20 Jul 2010 12:00:49 +0100
changeset 13 48780e181b38
parent 8 ae94777fff8f
permissions -rw-r--r--
Week 28 contribution of SDK documentation content. See release notes for details. Fixes bugs Bug 1897 and Bug 1522.

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  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-092C18D4-A525-5562-9BF6-41435E400290" xml:lang="en"><title>LibpThread Example - Using P.I.P.S OECORE </title><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>This example application shows, using a P.I.P.S. (P.I.P.S. Is POSIX
on the Symbian platform) program, the use of the LibpThread library
to demonstrate simple multi-threading and synchronisation. </p>
<p>The purpose is to create a basic multithreading example showing
the usage of the LibpThread APIs. This example also shows how multi-threading
is used to achieve concurrency in tasks and sharing of resources. </p>
<section id="GUID-026FD8D6-6C4A-5958-B289-775D4AE1E756-GENID-1-10-1-13-1-1-5-1-3-1-11-1-7-1-2-3"><title>Download</title> <p>Click on the following link to download the example: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/zips/guid-84e8baf2-57f1-4255-aeb8-a6ed0ed2145e.zip" scope="external"> LibpThreadExample.zip</xref></p><p>Click: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/guid-84e8baf2-57f1-4255-aeb8-a6ed0ed2145e.html" scope="peer">browse</xref> to view the example code. </p> </section>
<section id="GUID-7E7C4564-B10E-41F9-8A9D-D8A6C5E9C51C-GENID-1-10-1-13-1-1-5-1-3-1-11-1-7-1-2-4"><title>Description</title> <p>The following sections provide more information about the steps
that the example performs. </p> <p><b> Thread Synchronisation</b> </p> <p>The example creates three threads named ThreadOne, ThreadTwo
and ThreadThree. The threads write "One", "Two" and "Three" five times
in a text file. The text file, located in <filepath>epoc32\winscw\c\newfile.txt</filepath>, is used as a shared resource for all three threads. A mutex is
used to ensure that first ThreadOne writes in the file, then ThreadTwo
and then ThreadThree. If the mutex is not used all the threads can
simultaneously write in the file. This can be seen by commenting out <codeph>pthread_mutex_lock</codeph> and <codeph>pthread_mutex_unlock</codeph> in the code. </p> </section>
<section id="GUID-236CB272-E196-4A61-B627-ACFFC4B37AA1"><title>Related
APIs</title><p><xref href="GUID-94FEEC14-384E-364F-929F-0339FE559FB0.dita"><apiname>pthread_mutex_lock(pthread_mutex_t *)</apiname></xref> </p><p><xref href="GUID-E0AABD52-5A8F-3F49-A46D-5CE5BE975765.dita"><apiname>pthread_mutex_unlock(pthread_mutex_t *)</apiname></xref> </p><p><xref href="GUID-23868643-4C61-3661-843B-2D67C54CF163.dita"><apiname>pthread_join(pthread_t,void **)</apiname></xref></p><p><xref href="GUID-889CB456-6980-3B92-9350-0C6C8C9AC435.dita"><apiname>pthread_mutex_t</apiname></xref></p></section>
<section id="GUID-67A72761-1D92-46D1-B1C9-7455978BDE4E-GENID-1-10-1-13-1-1-5-1-3-1-11-1-7-1-2-6"><title>Build</title> <p>The Symbian build process describes how to build this example
application. </p> <p>The example builds an executable
called <filepath>LibpThreadExample.exe</filepath> in the standard
locations. </p> <p>To run the example, start <filepath>LibpThreadExample.exe</filepath> from the file system or from your IDE. After launching the executable,
depending on the emulator you are using, you may need to navigate
away from the application launcher or shell screen to view the console. </p> </section>
</conbody></concept>