Using << operator to write to both a file and cout

Question

I\'d like to overload << operator to write the value it takes to a file and cout. I have tried to do it with following code, but couldn\'t succeed it. It just writes t

Answer 1

If you are able to use it, you will find that, not unsurprisingly, the boost library has already done most of the hard work for you.

#include 
#include 
#include 
#include 

typedef boost::iostreams::tee_device teedev;
typedef boost::iostreams::stream, std::allocator< typename std::ostream::char_type > > tee_stream;

int main(int argc, char* argv[])
{
    std::ofstream of;
    of.open( "test.txt" );

    teedev td( of, std::cout );
    tee_stream ts(td);

    ts << "!!!Hello World!!!" << std::endl;

    return 0;
}