I make this treat because you are closing my other before i get my answer. Here is my answer clear and exactly what i want to do!

I wanna create a usb driver, so my own C application be able to get into my flash drive and take information from the imported flash drive. OS: Windows

Please don't close it again I still cant find my answer...

more details

I start my app/which contains my USB driver/ i plug-in my flash and its shows in Explorer that this drive is plugged and it is accessible, while that's happening, my app is checking that file data.txt EXIST if that file exist, program run next function, if not program, my program runs down/exit/! I hope that this helps understanding my idea...