title: How to know what file is opened by an application at any time?
body: <p>I'm new here, so I don't have the time to contribute before I ask for u guys' help, so pardon me for that.</p>
  
  <p>I'm not sure if this can be done, but I would like to find out the opened file(s) of an application.</p>
  
  <p>Here I don't mean the "internal" opened files, but are those that are opened by the end-user (either by invoking the handling app thru file-assoc, or explicitely inside the app). Think *.cs or *.vb files in Visual Studio (yeah I'm an MS guy) or text files in Notepad.</p>
  
  <p>I've looked at "verbs" in the Win Shell MSDN doc, but it only mentions the invoking, and no way to inspect info of invoked verbs. I also looked at DDE, but it looks like a general purpose facility and does not fit into my case here.</p>
  
  <p>I have to say that my situation is difficult to be solved by Googling because of the lack of unique key words, so this would definitely needs human attention :)</p>
  
  <p>Thanks</p>