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buffered_write_stream::write_some (2 of 2 overloads)

Write the given data to the stream. Returns the number of bytes written, or 0 if an error occurred and the error handler did not throw.

    typename ConstBufferSequence>
std::size_t write_some(
    const ConstBufferSequence & buffers,
    boost::system::error_code & ec);