Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

libs/test/doc/src/examples/example24.cpp

#include <iostream>
#include <boost/test/included/prg_exec_monitor.hpp> 

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int cpp_main( int, char* [] ) // note name cpp_main, not main.
{
    std::cout << "Hello, world\n";

    return 0;
}

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