multiple threads writing to std::cout or std::cerr

Question

I have OpenMP threads that write to the console via cout and cerr. This of course is not safe, since output can be interleaved. I could do something like

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Answer 1

I don't have enough reputation to post a comment, but I wanted to post my addition to the AtomicWriter class to support std::endl and allow for other streams to be used besides std::cout. Here it is:

class AtomicWriter {
    std::ostringstream st;
    std::ostream &stream;
public:
    AtomicWriter(std::ostream &s=std::cout):stream(s) { }
    template 
    AtomicWriter& operator<<(T const& t) {
        st << t;
        return *this;
    }
    AtomicWriter& operator<<( std::ostream&(*f)(std::ostream&) ) {
        st << f;
        return *this;
    }
    ~AtomicWriter() { stream << st.str(); }
};