Block device operations
File system operations
The ECF_CalculateFreeSpace function calculates the amount of free disk space on a mounted filesystem.
This is the drive letter of the file system you which to calculate the free space of. E.g. 'A'
This is a pointer to a DWORD that will receive the number of free sectors.
This is a pointer to a WORD that will receive the sector size. This parameter is not mandatory and may be NULL.
Returns one of the ECF error codes (ECFERR_SUCCESS on success)
ECF_CalculateFreeSpace needs to scan the entire FAT table to get an accurate count of the number of free sectors which may take some time.