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ECF_CalculateFreeSpace
The ECF_CalculateFreeSpace function calculates the amount of free disk space on a mounted file system.
ECF_ErrorCode ECF_CalculateFreeSpace(
   char driveLetter,
   uint32_t *pFreeSectors,
   uint16_t *pSectorSize
);
Parameters
driveLetter
This is the drive letter of the file system you which to calculate the free space of. E.g. 'A'
pFreeSectors
This is a pointer to a uint32_t that will receive the number of free sectors.
pSectorSize
This is a pointer to a uint16_t that will receive the sector size. This parameter is not mandatory and may be NULL.
Return value
Returns one of the EcFAT error codes (ECFERR_SUCCESS on success)
Remarks
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.