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<H2>35.5 Synchronizing the Standard Iostream Objects</H2>
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<P>The predefined Standard Iostream objects <SAMP>std::cin</SAMP>, <SAMP>std::cout</SAMP>, <SAMP>std::cerr</SAMP>, and <SAMP>std::clog</SAMP> , and their wide character counterparts, <SAMP>std::wcin</SAMP>, <SAMP>std::wcout</SAMP>, <SAMP>std::wcerr</SAMP>, and <SAMP>std::wclog</SAMP>, are examples of synchronized streams:</P>
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<LI><P CLASS="LIST"><SAMP>std::cin</SAMP> is tied to <SAMP>std::cout</SAMP>; that is, before each input operation on <SAMP>std::cin</SAMP>, the output stream <SAMP>std::cout</SAMP> is forced to flush its buffer.</P></LI>
<LI><P CLASS="LIST"><SAMP>std::cerr</SAMP> is synchronized using the <SAMP>std::ios_base::unitbuf</SAMP> format flag; that is, after each output to <SAMP>std::cerr</SAMP>, its buffer is flushed.</P></LI>
<LI><P CLASS="LIST"><SAMP>std::clog</SAMP> is connected to the same output channel and thus behaves like <SAMP>std::cerr</SAMP>, except that it is not synchronized with any of the other standard streams; that is, it does not have the <SAMP>std::ios_base::unitbuf</SAMP> flag set.</P></LI>
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