FSCK_EXFAT(8) System Manager's Manual FSCK_EXFAT(8)

fsck_exfat — Verify and repair ExFAT file systems.

fsck_exfat -q device ...

fsck_exfat [-f] [-p] [-y | -n] [-g | -x] [-S -path_prefix] [-d] device ...

The fsck_exfat utility verifies and repairs ExFAT file systems.

The first form of fsck_exfat quickly checks the specified file systems to determine whether they were cleanly unmounted.

The second form of fsck_exfat checks the specified file systems and tries to repair all detected problems, requesting confirmation before making any changes. The default behavior is to always ask for confirmation of each change. Use the -n or -y options to override this default behavior.

The device parameter(s) should be a path to a "raw" disk device (a character special device), such as /dev/rdisk1s1. If you specify a "non-raw" path (a block special device) such as /dev/disk1s1, or just the disk name such as disk1s1, they will automatically be converted to the corresponding raw disk device (/dev/rdisk1s1).

The options are as follows:

Causes fsck_exfat to quickly check whether the volume was unmounted cleanly. If the volume was unmounted cleanly, then the exit status is 0. If the volume was not unmounted cleanly, then the exit status will be non-zero. In either case, a message is printed to standard output describing whether the volume was clean or dirty.
This option is ignored by fsck_exfat and is present only for compatibility with programs that check other file system types for consistency.
Preen the specified file systems. This option is ignored by fsck_exfat and is present only for compatibility with programs that check other file system types for consistency.
Causes fsck_exfat to assume yes as the answer to all questions. It will attempt to repair all problems that are found.
Causes fsck_exfat to assume no as the answer to all questions. The device will be opened read-only, and no repairs will be made.
Causes fsck_exfat to produce its output in GUI-compatible form. Each message is printed as a tuple containing the kind of message, the message string, and number of parameters to the message string. Any parameters to the message string are printed on subsequent lines. The message string uses NSLog-like substitutions. This output format is used by applications such as Disk Utility.
Causes fsck_exfat to produce its output in an XML-like form. Each message is printed as a plist(5) containing a message type, verbosity, message number, and message string. The message string uses NSLog-like substitutions. For message strings that contain parameters, an array of dictionaries is output. This output format is used by applications such as Disk Utility. It may be used by other kinds of applications which wish to parse the output of fsck_exfat.
Causes fsck_exfat to produce extra debugging output. This generally contains additional details about problems found. When writing bug reports for fsck_exfat, it is usually helpful to include the output generated from this option.
path_prefix
Causes fsck_exfat to create a shadow file containing all metadata read from the device. This functionality is intended for inclusion with bug reports regarding excpetional problems. One file is created for each checked device. A shadow file's name is created by taking path_prefix, appending a - character, and then appending the of the device being checked. For instance, given a path_prefix of ./metadata, a check of disk would create the shadow file . Note that the shadow file captures all metadata as read from disk. In some cases with large volumes, fsck_exfat will limit its cache size and re-read metadata from disk at different phases of the repair process. If the repair process has repaired the metadata, the shadow file will capture its state as last read from disk. For optimal debug value, the shadow file should be captured in conjunction with the -n option. This file will be created as a sparse file, if it is on a file system supporting sparse files, such as . The shadow file does not capture file contents. However be aware Extreme care should be taken before sharing the shadow file with others.

mount_exfat(8), fsck(8)

The fsck_exfat utility first appeared in Mac OS X 10.6.3.

January 19, 2010 Darwin