/root/tmp/opm-core-release-2015.10-final/opm/core/utility/NullStream.hpp

Output stream that ignores everything written to it.

Use this stream if you want to disable output without having a lot of conditionals in your code.

Since the null stream has no state, there is no point in instantiating your own; simply use this reference instead.

std::ostream& outp = (quiet ? Opm::null_stream : std::cerr);
outp << "Hello, World!" << std::endl;