Need an explanation

[Day Vide]

Hey, I found some code on the internet and there is something I don't
understand. Why is there two colons (::) in front of the GetSystemMetrics
function.

  double fScreenWidth = ::GetSystemMetrics( SM_CXSCREEN )-1;
  double fScreenHeight = ::GetSystemMetrics( SM_CYSCREEN )-1;

Thanks

[jonnin]

:: is the scope operator.
It is probably unnecessary but the author wanted to be sure that if two versions of that function existed, use the one in the current scope.

[xismn]

This is an example of a scope resolution operator without a scope qualifier.
In this case, it refers to the global scope.

[integralfx]

The scope operator without a name is known as the global scope operator. This link explains it pretty well: http://stackoverflow.com/questions/75213/scope-resolution-operator-without-a-scope?rq=1

[Day Vide]

Ohhh thanks guys