Return Code of the File Functions

On the FatFs API, most of file functions return common result code as enum type. When a function succeeded, it returns zero, otherwise returns non-zero value that indicates type of error.

FR_OK (0)

The function succeeded.

FR_DISK_ERR

An unrecoverable error occured in the lower layer (disk I/O functions).

FR_INT_ERR

Assertion failed. An insanity is detected in the internal process. One of the following possibilities are suspected.

• There is any error of the FAT structure on the volume.
• Work area (file system object, file object or etc...) is broken by stack overflow or any other application. This is the reason in most case.
• An FR_DISK_ERR has occured on the file object.

FR_NOT_READY

The disk drive cannot work due to incorrect medium removal or disk_initialize function failed.

FR_NO_FILE

Could not find the file.

FR_NO_PATH

Could not find the path.

FR_INVALID_NAME

The given string is invalid as the path name.

FR_DENIED

The required access was denied due to one of the following reasons:

• Write mode open against the file with read-only attribute.
• Deleting the file or directory with read-only attribute.
• Deleting the non-empty directory or current directory.
• Reading the file opened without FA_READ flag.
• Any modification to the file opened without FA_WRITE flag.
• Could not create the file or directory due to the directory table is full.
• Could not create the directory due to the volume is full.

FR_EXIST

Any object that has the same name is already existing.

FR_INVALID_OBJECT

The given file/directory object structure is invalid.

FR_WRITE_PROTECTED

Any write mode action against write-protected media.

FR_INVALID_DRIVE

Invalid drive number is specified. (Related option: _VOLUMES)

FR_NOT_ENABLED

Work area for the logical drive has not been registered by f_mount function.

FR_NO_FILESYSTEM

There is no valid FAT volume on the drive.

FR_MKFS_ABORTED

The f_mkfs function aborted before start in format due to a reason as follows:

• The disk size is too small.
• Not allowable cluster size for this disk. This can occure when number of clusters gets near the 0xFF7 and 0xFFF7.

FR_TIMEOUT

The function canceled due to a timeout of thread-safe control. (Related option: _TIMEOUT)

FR_LOCKED

The file access is rejected by file sharing control. (Related option: _FS_LOCK)

FR_NOT_ENOUGH_CORE

Not enough memory for the operation. There is one of the following reasons:

• Could not allocate a memory for LFN working buffer. (Related option: _USE_LFN)
• Given table size is insufficient for the required size.

FR_TOO_MANY_OPEN_FILES

Number of open files has been reached maximum value and no more file can be opened. (Related option: _FS_LOCK)

FR_INVALID_PARAMETER

The given parameter is invalid or there is any inconsistent.