I’m trying to test one my applications that installs various things onto the system. As such, there is a minimum required disk space for it to work correctly. In order to determine this threshold, I wished to simulate various low disk-space scenarios. I used the below command to create a large sparse file (i.e. not suitable as an actual data source) to fill the disk.
fsutil file createnew c:\temp\bigfile.dat <size_in_bytes>