the "friend" function .... ?

[twomers]

Hi, I accidently came accross the friend function when I was initilizing a variable ... does anyone know what it does and how to use it?

[ZuK]

If you want to give ( possibly unrelated ) classes or functions acces to protected members of a class you use the keyword friend.
Commonly used for stream inserters/extractors.
e.g

class foo{
public: 
  foo():v(0) {}
  friend ostream & operator << ( ostream & str, foo & inst );
protected:
  int v;
};

// without beeing friend to foo the stream inserter would not be allowed to access inst.v
inline ostream & operator << ( ostream & str, foo & inst ) {
   return str << inst.v;
}

Kurt

[jlf029]

Generally used in classes to give functions or other classes access to the private data members