FSCK

Section: Linux Programmer's Manual (8)
Updated: 2 July 1996

NAME

fsck.minix - a file system consistency checker for Linux

SYNOPSIS

fsck.minix [-larvsmf] device

DESCRIPTION

fsck.minix performs a consistency check for the Linux MINIX filesystem. The current version supports the 14 character and 30 character filename options.

The program assumes the file system is quiescent. fsck.minix should not be used on a mounted device unless you can be sure nobody is writing to it (and remember that the kernel can write to it when it searches for files).

The device will usually have the following form:


/dev/hda[1-63] (IDE disk 1)
/dev/hdb[1-63] (IDE disk 2)
/dev/sda[1-15] (SCSI disk 1)
/dev/sdb[1-15] (SCSI disk 2)

If the file system was changed (i.e., repaired), then fsck.minix will print "FILE SYSTEM HAS CHANGED" and will sync(2) three times before exiting. Since Linux does not currently have raw devices, there is no need to reboot at this time.

WARNING

fsck.minix should not be used on a mounted filesystem. Using fsck.minix on a mounted filesystem is very dangerous, due to the possibility that deleted files are still in use, and can seriously damage a perfectly good filesystem! If you absolutely have to run fsck.minix on a mounted filesystem (i.e., the root filesystem), make sure nothing is writing to the disk, and that no files are "zombies" waiting for deletion.

OPTIONS

-l: Lists all filenames
-r: Performs interactive repairs
-a: Performs automatic repairs (this option implies -r), and serves to answer all of the questions asked with the default. Note that this can be extremely dangerous in the case of extensive file system damage.
-v: Verbose
-s: Outputs super-block information
-m: Activates MINIX-like "mode not cleared" warnings
-f: Force file system check even if the file system was marked as valid (this marking is done by the kernel when the file system is unmounted).

DIAGNOSTICS

There are numerous diagnostic messages. The ones mentioned here are the most commonly seen in normal usage.

If the device does not exist, fsck.minix will print "unable to read super block". If the device exists, but is not a MINIX file system, fsck.minix will print "bad magic number in super-block".

EXIT CODES

The exit code returned by fsck.minix is the sum of the following:

0: No errors
3: File system errors corrected, system should be rebooted if file system was mounted
4: File system errors left uncorrected
8: Operational error
16: Usage or syntax error

In point of fact, only 0, 3, 4, 7, 8, and 16 can ever be returned.

AUTHOR

Linus Torvalds (torvalds@cs.helsinki.fi)
Error code values by Rik Faith (faith@cs.unc.edu)
Added support for file system valid flag: Dr. Wettstein (greg%wind.uucp@plains.nodak.edu)
Check to prevent fsck of mounted filesystem added by Daniel Quinlan (quinlan@yggdrasil.com)
Minix v2 fs support by Andreas Schwab (schwab@issan.informatik.uni-dortmund.de), updated by Nicolai Langfeldt (janl@math.uio.no)
Portability patch by Russell King (rmk@ecs.soton.ac.uk).

AVAILABILITY

The fsck.minix command is part of the util-linux-ng package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.

This document was created by man2html, using the manual pages.
Time: 07:35:42 GMT, March 26, 2013