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dcheck(8) [ultrix man page]

dcheck(8)						      System Manager's Manual							 dcheck(8)

Name
       dcheck - check directory consistency

Syntax
       /etc/dcheck [ -i numbers ] [ filesystem ]

Description
       The command is obsoleted for normal consistency checking by

       The command 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 direc-
       tory, 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.

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 nothing.  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.

Restrictions
       Since is inherently two-pass in nature, extraneous diagnostics may be produced if applied to active file systems.

Files
       Default file systems vary with installation.

See Also
       fs(5), clri(8), fsck(8), icheck(8), ncheck(8)

																	 dcheck(8)

Check Out this Related Man Page

ICHECK(1M)																ICHECK(1M)

NAME
icheck - file system storage consistency check SYNOPSIS
icheck [ -s ] [ -b numbers ] [ filesystem ] DESCRIPTION
Icheck examines a file system, builds a bit map of used blocks, and compares this bit map against the free list maintained on the file sys- tem. If the file system is not specified, a set of default file systems is checked. The normal output of icheck includes a report of The total number of files and the numbers of regular, directory, block special and character special files. The total number of blocks in use and the numbers of single-, double-, and triple-indirect blocks and directory blocks. The number of free blocks. The number of blocks missing; i.e. not in any file nor in the free list. The -s option causes icheck to ignore the actual free list and reconstruct a new one by rewriting the super-block of the file system. The file system should be dismounted while this is done; if this is not possible (for example if the root file system has to be salvaged) care should be taken that the system is quiescent and that it is rebooted immediately afterwards so that the old, bad in-core copy of the super- block will not continue to be used. Notice also that the words in the super-block which indicate the size of the free list and of the i- list are believed. If the super-block has been curdled these words will have to be patched. The -s option causes the normal output reports to be suppressed. Following the -b option is a list of block numbers; whenever any of the named blocks turns up in a file, a diagnostic is produced. Icheck is faster if the raw version of the special file is used, since it reads the i-list many blocks at a time. FILES
Default file systems vary with installation. SEE ALSO
dcheck(1), ncheck(1), filsys(5), clri(1) DIAGNOSTICS
For duplicate blocks and bad blocks (which lie outside the file system) icheck announces the difficulty, the i-number, and the kind of block involved. If a read error is encountered, the block number of the bad block is printed and icheck considers it to contain 0. `Bad freeblock' means that a block number outside the available space was encountered in the free list. `n dups in free' means that n blocks were found in the free list which duplicate blocks either in some file or in the earlier part of the free list. BUGS
Since icheck is inherently two-pass in nature, extraneous diagnostics may be produced if applied to active file systems. It believes even preposterous super-blocks and consequently can get core images. ICHECK(1M)

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