DCHECK(1M) DCHECK(1M)
NAME
dcheck - file system directory consistency check
SYNOPSIS
dcheck [ -i numbers ] [ filesystem ]
DESCRIPTION
Dcheck reads the directories in a file system and compares
the link-count in each i-node with the number of directory
entries by which it is referenced. If the file system is
not specified, a set of default file systems is checked.
The -i flag is followed by a list of i-numbers; when one
of those i-numbers turns up in a directory, the number,
the i-number of the directory, and the name of the entry
are reported.
The program is fastest if the raw version of the special
file is used, since the i-list is read in large chunks.
FILES
Default file systems vary with installation.
SEE ALSO
icheck(1), filsys(5), clri(1), ncheck(1)
DIAGNOSTICS
When a file turns up for which the link-count and the num-
ber of directory entries disagree, the relevant facts are
reported. Allocated files which have 0 link-count and no
entries are also listed. The only dangerous situation
occurs when there are more entries than links; if entries
are removed, so the link-count drops to 0, the remaining
entries point to thin air. They should be removed. When
there are more links than entries, or there is an allo-
cated file with neither links nor entries, some disk space
may be lost but the situation will not degenerate.
BUGS
Since dcheck is inherently two-pass in nature, extraneous
diagnostics may be produced if applied to active file sys-
tems.
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