Const Correctness in C++

// value being pointed cannot be changed:
const char * ptr;

// address of the pointer cannot be changed, 
// but the value being pointed can be
char * const ptr;

// both value and the address of the pointer cannot be changed
const char * const ptr;

• http://www.possibility.com/Cpp/const.html
• http://www.codeguru.com/cpp/cpp/cpp_mfc/general/article.php/c6967/Constant-Pointers-and-Pointers-to-Constants.htm