Ho il seguente cod:
codice:
// Screen.h
#ifndef SCREEN_H
#define SCREEN_H

class Screen
{
    public:
        Screen(int x, int y);
        ~Screen();
        inline int cursor() const { return _cursor; }
    private:
        int _cursor,_x,_y;
};

#endif
codice:
 // Screen.cpp
#include "Screen.h"

Screen::Screen(int x, int y): x(_x), y(_y)
{
    _cursor = x/y;
}

Screen::~Screen()
{
    delete _x, _y, _cursor;
}
codice:
 
// Test.cpp
#include <cstdio>
#include <iostream>
#include "Screen.h"

using namespace std;

int main()
{
    int i=5, j=10;
    Screen *ptrSc = new Screen(i, j);
    cout << ptrSc->cursor() <<endl;    
    system("PAUSE");
    return 0;
}
Ma mi da:
Compilatore: C++ Optimized Maximum
Esecuzione di g++.exe...
g++.exe "C:\Documents and Settings\Admin\Desktop\Screen\Test.cpp" -o "C:\Documents and Settings\Admin\Desktop\Screen\Test.exe" -fexpensive-optimizations -O2 -I"C:\Dev-Cpp\include\c++" -I"C:\Dev-Cpp\include\c++\mingw32" -I"C:\Dev-Cpp\include\c++\backward" -I"C:\Dev-Cpp\include" -L"C:\Dev-Cpp\lib"
C:\DOCUME~1\Admin\IMPOST~1\Temp/ccY5aaaa.o(.text+0x39):Test.cpp: undefined reference to `Screen::Screen(int, int)'

Esecuzione terminata