Well, there is the obvious of looking (humor....)
This is a Win API call. The lvwin utilities does not appear to contain the proper call to get this information. I would suggest determining what you need to do If you just need to show the window, then do that instead, you won't have to worry about whether or not it is already showing.
However, if what you need is to know if the window is minimized, and aren't going to act to show or hide the window, then you will need to research the user32.dll and win32.dll functions to get the exact function you need, and the parameters for that function.
If you aren't in windows, congratulations. You should have better luck interfacing with the opsys, or at least, in getting the information you need to do this.
Good luck, and please let us know how you do.