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A simple echo program

The following small program accepts streams from the console and prints out as soon as we hit enter.

#include

template < typename In, typename Out >
void Echo(In& in, Out& out)
{
    out << in.rdbuf();
}

int main()
{
    Echo(std::cin, std::cout);
    return 0;
}

So, the rdbuf() returns a pointer to the underlying basic_streambuf for the input stream and prints it out again on the console.

The program runs in a loop until we break it by Ctrl+C.

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