Paste function in windows.

There is no such thing. This is not how it works. You don't need to "know destination", you provide the destination using Windows API.

The clipboard operations simply allow you to put data from the clipboard or retrieve data from clipboard, if any, depending on the required clipboard format. That is, the primary destination is just the memory of a calling process. When you obtain the data, you can put it anywhere you want. You can also register new data format and define how the clipboard handles the data of such custom type. Please start here:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms648709%28v=vs.85%29.aspx[^].

—SA