C++ scope

Variables store the state of a program. We know that it's the way a program 'remembers' something. This 'state' is also notoriously prone to side-effects. A variable altered in one place can have un-intended consequence in another.

The 'scope' of a variable determines where it can be accessed. A variable with lower scope can be changed with higher confidence (= lower side-effects).

See here for an introduction to scope in C++

C++ also scopes variables in classes. See here for details.

Is the scope of a variable checked at compile-time or run-time?

In other words, can we access a private data member if the class returns a pointer to it?

class PrivacyViolator {

  private:

    char name[256];

  public:

    char* getName() {

      return name;

    }

};

Can I call getName from outside this class and change its contents?

    PrivacyViolator p;

    char* s = p.getName();

    char source[] = "Accessed private variable";

    strcpy_s(s, sizeof(source), source);

Why does the above code work, though it copies a string to an uninitialized variable?

Leave your thoughts below. Then go on to control structures in C++.