rtrimws: can't compile in g++

[eric]

Dear advanced c++ programers:

  I copied and tested a piece simple Trimming string code from book c+
+ cookbook in chapter4, section2
Example 4-4:Trim trailing whitespace.  You can download and try it by
yourself.
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http://examples.oreilly.com/9780596007614/
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in my g++ 4.5.2, compiler reponse
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4-4.cpp: In function ‘void rtrimws(std::string&)’:
4-4.cpp:21:21: error: too many arguments to function ‘void
rtrimws(std::string&)’
4-4.cpp:20:6: note: declared here
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according to the book, all book example code is compiled success in
Visual C++ compiler
so, please help
Eric