FSCK_HFS(8)
NAME
fsck_hfs -- HFS file system consistency check
SYNOPSIS
fsck_hfs -q [-df] special ... fsck_hfs -p [-df] special ... fsck_hfs [-n | -y | -r] [-dfgl] [-m mode] [-c size] special ...
DESCRIPTION
The fsck_hfs utility verifies and repairs standard HFS and HFS+ file systems.
The first form of fsck_hfs quickly checks the specified file systems to
determine whether they were cleanly unmounted.
The second form of fsck_hfs preens the specified file systems. It is
normally started by fsck(8) run from /etc/rc.boot during automatic
reboot, when a HFS file system is detected. When preening file systems,
fsck_hfs will fix common inconsistencies for file systems that were not
unmounted cleanly. If more serious problems are found, fsck_hfs does not
try to fix them, indicates that it was not successful, and exits.
The third form of fsck_hfs checks the specified file systems and tries to
repair all detected inconsistencies.
If no options are specified fsck_hfs will always check and attempt to fix
the specified file systems.
- The options are as follows:
- -c size Specify the size of the cache used by fsck_hfs internally.
Bigger size can result in better performance but can result in deadlock when used with -l option. Size can be specified as a decimal, octal, or hexadecimal number. If the
number ends with a ``k'', ``m'', or ``g'', the number is
multiplied by 1024 (1K), 1048576 (1M), or 1073741824 (1G), respectively. - -d Display debugging information. This option may provide
- useful information when fsck_hfs cannot repair a damaged file system.
- -f When used with the -p option, force fsck_hfs to check
- `clean' file systems, otherwise it means force fsck_hfs to check and repair journaled HFS+ file systems.
- -g Causes fsck_hfs to generate it's output strings in GUI for
- mat. This option is used when another application with a
graphical user interface (like Mac OS X Disk Utility) is
invoking the fsck_hfs tool. - -l Lock down the file system and perform a test-only check.
- This makes it possible to check a file system that is currently mounted, although no repairs can be made.
- -m mode Mode is an octal number that will be used to set the per
- missions for the lost+found directory when it is created.
The lost+found directory is only created when a volume is
repaired and orphaned files or directories are detected.
fsck_hfs places orphaned files and directories into the lost+found directory (located at the root of the volume).
The default mode is 01777. - -p Preen the specified file systems.
- -q Causes fsck_hfs 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. - -y Always attempt to repair any damage that is found.
- -n Never attempt to repair any damage that is found.
- -r Rebuild the catalog file on the specified file system.
- This option currently will only work if there is enough
contiguous space on the specified file system for a new
catalog file and if there is no damage to the leaf nodes in the existing catalog file. - Because of inconsistencies between the block device and the buffer cache, the raw device should always be used.
SEE ALSO
BUGS
fsck_hfs is not able to fix some inconsistencies that it detects.
HISTORY
- The fsck_hfs command appeared in Mac OS X Server 1.0 .