<?xml version="1.0" encoding="utf-8"?>

<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

<!-- This component and the accompanying materials are made available under the terms of the License 

"Eclipse Public License v1.0" which accompanies this distribution, 

and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

<!-- Initial Contributors:

    Nokia Corporation - initial contribution.

Contributors: 

-->

<!DOCTYPE concept

  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

<concept id="GUID-9BFF0271-F5C3-45B6-AD4D-9179107F300A" xml:lang="en"><title>Open

C Producer Consumer Example</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>OpenCProducerConsumerEx is a hybrid application that depicts solution for

producer consumer problem using Open C. This application uses main() as an

entry point for the application. It uses <codeph>libc</codeph> and <codeph>libpthread</codeph> </p>

<section id="GUID-026FD8D6-6C4A-5958-B289-775D4AE1E756-GENID-1-10-1-11-1-1-5-1-3-1-11-1-13-1-2-2"><title>Download</title> <p>Click

on the following link to download the example: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/zips/guid-b9259541-c444-400a-8f6e-8daaa5381a79.zip" scope="external">opencproducerconsumerex.zip</xref></p><p>Click: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/guid-b9259541-c444-400a-8f6e-8daaa5381a79.html" scope="peer">browse</xref> to view the example code. </p> </section>

<section id="GUID-7E7C4564-B10E-41F9-8A9D-D8A6C5E9C51C-GENID-1-10-1-11-1-1-5-1-3-1-11-1-13-1-2-3"><title>Design and

Implementation</title> <p>The following sections provide information about

the implementation of the example. </p> <p><b>Capabilities</b> </p> The program

capability is defined in: <filepath>ProducerConsumer.mmp</filepath> (EXE -

application):<codeph> CAPABILITY NONE</codeph>. <p><b>Implementation details

of EXE</b> </p>This is a simple console based application. Main thread of

the application will create a thread named as Producer that will produce the

item and push it on to the stack. There will be N consumers which want to

consume some N(i) items from the Producer. Producer will produce N items at

a time and pushes them to the stack and totally it will produce sum(N(i))

items. The consumer thread will try to pop items from the stack and each consumer

will pop N(i) items from the stack. The application will create one thread

for each consumer. Producer and all the consumer threads will be synchronized

using a semaphore. The main thread, Producer and the consumer codes are pure

C-code. the stack used by Producer and the consumer threads is Standard C++

code. Apart from these threads, there is another thread named as Observer

that is created using Symbian platform API. Producer and the consumers will

establish a message queue with this thread and Observer will read message

from all other threads and will log them to a file wich is opened/written

using Symbian APIs. Hence, this application is a hybrid application with:

 <p>Standard C code -&gt; <filepath>Consumer.c</filepath>, <filepath>Producer.c</filepath>, <filepath>ProducerConsumer.c</filepath>, <filepath>CommanHeader.h</filepath> </p><p>Standard C++ code -&gt; <filepath>Stack.cpp</filepath>,<filepath>Stack.h</filepath>, <filepath>CommanHeader.h</filepath></p><p>Symbian

platform code that uses <codeph>libc</codeph> APIs and Observer.cpp.</p><p> 

The application has its own icon and can be launched from the UI both in the

emulator and in the device. </p><p><b>API Usage</b></p><p><codeph>string APIs</codeph> </p><p><codeph>IPC

APIs (message queue and semaphore)</codeph> </p><p> <codeph>Threading APIs

(from pthread)</codeph> </p><p><codeph>console I/O APIs</codeph>  </p><p><codeph>File

APIs of Symbian platform</codeph></p><p> <codeph>Threading APIs of Symbian

platform</codeph></p></section>

<section id="GUID-67A72761-1D92-46D1-B1C9-7455978BDE4E-GENID-1-10-1-11-1-1-5-1-3-1-11-1-13-1-2-4"><title>Building and

Using</title> To build the OpenCProducerConsumerEx application, go to the

OpenCProducerConsumerEx\group directory and build the application. The definition

for the whole application can be found in the<filepath> bld.inf</filepath>in

the group subdirectory of the applications main directory. <p>The application

is simple console based application. It has its own default icon and can be

launched from the UI both in the emulator and in the device. The application

can be launched by: Executing OpenCProducerConsumerEx from eshell. Clicking

default icon with display text OpenCProducerConsumerEx within the install

folder launcher application. </p></section>