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copied!<p>I don't know if this is correct solution, but I inherited from std::ostream this way. It uses a buffer inherited from std::basic_streambuf and gets 64 characters at a time (or less if flushed) and sends them to a generic putChars() method where the actual handling of data is done. It also demonstrates how to give user data.</p> <p><a href="http://ideone.com/AFzNdO" rel="nofollow noreferrer">Live Example</a></p> <pre><code>#include <streambuf> #include <ostream> #include <iostream> //#define DEBUG class MyData { //example data class, not used }; class MyBuffer : public std::basic_streambuf<char, std::char_traits<char> > { public: inline MyBuffer(MyData data) : data(data) { setp(buf, buf + BUF_SIZE); } protected: // This is called when buffer becomes full. If // buffer is not used, then this is called every // time when characters are put to stream. inline virtual int overflow(int c = Traits::eof()) { #ifdef DEBUG std::cout << "(over)"; #endif // Handle output putChars(pbase(), pptr()); if (c != Traits::eof()) { char c2 = c; // Handle the one character that didn't fit to buffer putChars(&c2, &c2 + 1); } // This tells that buffer is empty again setp(buf, buf + BUF_SIZE); return c; } // This function is called when stream is flushed, // for example when std::endl is put to stream. inline virtual int sync(void) { // Handle output putChars(pbase(), pptr()); // This tells that buffer is empty again setp(buf, buf + BUF_SIZE); return 0; } private: // For EOF detection typedef std::char_traits<char> Traits; // Work in buffer mode. It is also possible to work without buffer. static const size_t BUF_SIZE = 64; char buf[BUF_SIZE]; // This is the example userdata MyData data; // In this function, the characters are parsed. inline void putChars(const char* begin, const char* end){ #ifdef DEBUG std::cout << "(putChars(" << static_cast<const void*>(begin) << "," << static_cast<const void*>(end) << "))"; #endif //just print to stdout for now for (const char* c = begin; c < end; c++){ std::cout << *c; } } }; class MyOStream : public std::basic_ostream< char, std::char_traits< char > > { public: inline MyOStream(MyData data) : std::basic_ostream< char, std::char_traits< char > >(&buf), buf(data) { } private: MyBuffer buf; }; int main(void) { MyData data; MyOStream o(data); for (int i = 0; i < 8; i++) o << "hello world! "; o << std::endl; return 0; } </code></pre>

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