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<!DOCTYPE concept
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-C7589C93-B517-4251-ACFB-B03E07993242" xml:lang="en"><title>Hybrid
Applications with Symbian C++ and Standard C</title><shortdesc/><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>If the developers want to use any of the P.I.P.S. APIs while writing some
Symbian application, they need to link to the corresponding library. The only
difference being that the developer does not have to link with the <codeph>STATICLIBRARY</codeph> <filepath>libcrt0.lib</filepath> in
the MMP file.</p>
<p>There are no additional P.I.P.S. specific changes that need to be done
in the source file in this case. This is possible, because the P.I.P.S. developer
of does not have to call any library initialization routine before use or
cleanup routine after use.</p>
<p>Some of the P.I.P.S. APIs assume that a cleanup stack is created and there
is a top-level TRAP. If the developer does not create either of the two, calling
such APIs may lead to application crash. </p>
<note>In a hybrid application, the user must make sure that the
cleanup stack is created and a top-level TRAP marker is done.</note>
<p>Hybrid application can also contain threads created using both <xref href="GUID-B0E661BC-4058-3256-B9C3-5A4FD52F6DE5.dita#GUID-B0E661BC-4058-3256-B9C3-5A4FD52F6DE5/GUID-6C840907-C3F7-34B7-97DB-CEDBA68EA277"><apiname>RThread::Create()</apiname></xref> and <codeph>pthread_create()</codeph>,
and can still use P.I.P.S. APIs in both the threads. In case of <xref href="GUID-B0E661BC-4058-3256-B9C3-5A4FD52F6DE5.dita#GUID-B0E661BC-4058-3256-B9C3-5A4FD52F6DE5/GUID-6C840907-C3F7-34B7-97DB-CEDBA68EA277"><apiname>RThread::Create()</apiname></xref> the
developer has to create cleanup stack and a top level TRAP for this thread
in the thread entry Function, if it is required; else this thread may crash
or panic. </p>
<p>An application can have both C++ and C source codes. In this case, in order
to give C linkage to C++ code- that is calling a function defined in a C++
file that may have C++ code, use extern “C”. For example:</p>
<codeblock xml:space="preserve">// File: sample.c
  void OtherFoo();
  
  void Foo() {
     OtherFoo();
  }

// File: useme.cpp
  
  extern “C” {
  void OtherFoo() {
     //Can use any C++ code here
     //Can use Symbian C++ code here
  }
  }
</codeblock>
</conbody></concept>