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<title>EPICS pvData C++</title>
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<h1 style="text-align: center">EPICS pvData C++<br />
Overview<br />
2010.08.10</h1>
CONTENTS
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<h2 style="text-align: center">Introduction</h2>
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<p>This project has the begining of the C++ implementation of pvData. The
following is done:</p>
<dl>
<dt>introspection interfaces</dt>
<dd>The introspection interfaces for clients are described.</dd>
<dt>introspection implementation</dt>
<dd>The following have been implemented: Type, ScalarType, Field,
Scalar</dd>
<dt>test</dt>
<dd>A test of Scalar.</dd>
<dt>As mentioned below there are problems with the current
implementation.</dt>
</dl>
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<h2 style="text-align: center">Building</h2>
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<p>The project is structured as an epics base client application. Edit
configure/RELEASE so that it references your EPICS base and then just
type:</p>
<pre> make</pre>
<p>At the top. Then execute the test in the bin directory.</p>
<p>pvDataApp has the following sub directories:</p>
<dl>
<dt>pv</dt>
<dd>pvData.h has the interface descriptions for client code.</dd>
<dt>factory</dt>
<dd>FieldCreateFactory.cpp has the current implementation</dd>
<dt>test</dt>
<dd>Has a test for the current implementation.</dd>
</dl>
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<h2 style="text-align: center">Questions about Classes</h2>
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<p>The pure virtual classes defined in pvData.h now work. But there are still
some things that are not so nice. Amoung these are:</p>
<ul>
<li>In FieldCreateFactory.cpp look for "WHY DO I". It asks why the derived
class must also define methods defined in the base class. If it does not
then a compilation error occurs. WHY??? </li>
<li>The toString methods have an argument of "std::string &buf" instead
of "std::string *". Does this seem correct?</li>
<li>Can arguments and return descriptions be defined better?</li>
<li>Is const present everywhere it should be? Remember that introspection
classes are immutable.</li>
<li>The code is NOT thread safe. When we decide for sure what thread/lock
support to choose I will fix this.</li>
</ul>
<p>HELP WILL BE GREATLY APPRECIATED. because I am still coming up to speed
with c++</p>
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<h2 style="text-align: center">Garbage Collection</h2>
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<p>Not yet implemented. Lets get class structure correct first.</p>
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