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    <p>I would implement the library in C++. If you need C access, then this is easily done by hand, by providing wrapper functions that take an additional "this" argument.</p> <p>Before you start though, read the <a href="http://swig.org" rel="nofollow">SWIG</a> documentation, in particular its limitations and things to avoid. If you design your C++ interface with SWIG in mind you can get the bindings for a lot of languages generated for you without effort.</p> <p><b>Edit</b>: Here is a quick example of a C wrapper for a C++ class. Let's say this is the C++ class to wrap, let's call it <code>test.h</code>:</p> <pre><code>class Test { public: Test(); int do_something(char* arg); private: is_valid(); // see below for why you need this method }; </code></pre> <p>This is your C header <code>test_c.h</code>:</p> <pre><code>typedef void* TestHandle; TestHandle newTest(); int deleteTest(TestHandle h); int Test_do_something(TestHandle h, char* arg); </code></pre> <p>And your C implementation will be a C++ file with C functions, let's say <code>test_c.cpp</code>:</p> <pre><code>extern "C" TestHandle newTest() { return (void*)new Test(); } extern "C" int deleteTest(TestHandle h) { Test* this = static_cast&lt;Test*&gt;(h); if (!this-&gt;is_valid()) return -1; // here we define -1 as "invalid handle" error delete this; return 0; // here we define 0 as the "ok" error code } extern "C" int Test_do_something(TestHandle h, char* arg) { Test* this = static_cast&lt;Test*&gt;(h); if (!this-&gt;is_valid()) return -1; // here we define -1 as "invalid handle" error return this-&gt;do_something(arg); } </code></pre> <p>The <code>is_valid()</code> method is there to guarantee that you are not passed a bad handle. For example, you can store a <a href="http://en.wikipedia.org/wiki/Magic_number_(programming)" rel="nofollow">magic number</a> in all your instances, then <code>is_valid()</code> just ensures the magic number is there.</p>
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    1. POI'm Making a set of frameworks. I want to support multiple programming languages
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    1. POI'm Making a set of frameworks. I want to support multiple programming languages
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    1. COI like the idea but could you show an example of C++ C wrapper like you are talking about?
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    2. COI have updated my answer with an C wrapper example.
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    3. COThank you this will work perfectly I'm new here when I get points i will vote you up but i can't till people quit voting me down ps: on a final question do you think it is possible to have the C wrapper in the same binary with the C++ classes,functions?
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