DCHECK(VIII) 2/8/75 DCHECK(VIII)
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
Currently, /dev/rrk2 and /dev/rrp0 are the default file
systems.
DIAGNOSTICS
When a file turns up for which the link-count and the number
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 allocated
file with neither links nor entries, some disk space may be
lost but the situation will not degenerate.
SEE ALSO
icheck (VIII), fs (V), clri (VIII), ncheck (VIII)
BUGS
Since dcheck is inherently two-pass in nature, extraneous
diagnostics may be produced if applied to active file
systems.