Writes bytes from the given buffer to the channel.
The maximum number of bytes that will be written is the
remaining() number of bytes in the buffer when the method
invoked. The bytes will be written from the buffer starting at the
buffer's position.
The call may block if other threads are also attempting to write on the
same channel.
Upon completion, the buffer's position() is updated to the
end of the bytes that were written. The buffer's limit()
is unmodified.
