- publishing free software manuals
An Introduction to GCC - for the GNU compilers gcc and g++
by Brian J. Gough, foreword by Richard M. Stallman
Paperback (6"x9"), 144 pages
ISBN 0954161793
RRP £12.95 ($19.95)

"Answers common questions and provides many useful hints" --- Dr. Gerald Pfeifer (SUSE) -- Technical Editor Get a printed copy>>>

7.3 Using the C++ standard library

An implementation of the C++ standard library is provided as a part of GCC. The following program uses the standard library string class to reimplement the Hello World program:

#include <string>
#include <iostream>

using namespace std;

main ()
  string s1 = "Hello,";
  string s2 = "World!";
  cout << s1 + " " + s2 << '\n';
  return 0;

The program can be compiled and run using the same commands as above:

$ g++ -Wall hellostr.cc
$ ./a.out 
Hello, World!

Note that in accordance with the C++ standard, the header files for the C++ library itself do not use a file extension. The classes in the library are also defined in the std namespace, so the directive using namespace std is needed to access them, unless the prefix std:: is used throughout (as in the previous section).

ISBN 0954161793An Introduction to GCC - for the GNU compilers gcc and g++See the print edition