32v 1m dcheck

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DCHECK(1M) UNIX Programmer's Manual DCHECK(1M)


    dcheck - file system directory consistency check


    dcheck [ -i numbers ] [ filesystem ]


    _D_c_h_e_c_k 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
    The program is fastest if the raw version of the special
    file is used, since the i-list is read in large chunks.


    Default file systems vary with installation.


    icheck(1), filsys(5), clri(1), ncheck(1)


    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.


    Since _d_c_h_e_c_k is inherently two-pass in nature, extraneous
    diagnostics may be produced if applied to active file sys-