GRPCK(8)		  System Management Commands		      GRPCK(8)



NAME
       grpck - verify integrity of group files

SYNOPSIS
       grpck [-r] [group shadow]

DESCRIPTION
       The grpck command verifies the integrity of the system authentication
       information. All entries in the /etc/group and /etc/gshadow are checked
       to see that the entry has the proper format and valid data in each
       field. The user is prompted to delete entries that are improperly
       formatted or which have other uncorrectable errors.

       Checks are made to verify that each entry has:

       o   the correct number of fields

       o   a unique group name

       o   a valid list of members and administrators

       The checks for correct number of fields and unique group name are
       fatal. If the entry has the wrong number of fields, the user will be
       prompted to delete the entire line. If the user does not answer
       affirmatively, all further checks are bypassed. An entry with a
       duplicated group name is prompted for deletion, but the remaining
       checks will still be made. All other errors are warnings and the user
       is encouraged to run the groupmod command to correct the error.

       The commands which operate on the /etc/group file are not able to alter
       corrupted or duplicated entries.  grpck should be used in those
       circumstances to remove the offending entry.

OPTIONS
       By default, grpck operates on the files /etc/group and /etc/gshadow.
       The user may select alternate files with the group and shadow
       parameters. Additionally, the user may execute the command in read-only
       mode by specifying the -r flag. This causes all questions regarding
       changes to be answered no without user intervention.  grpck can also
       sort entries in /etc/group and /etc/gshadow by GID. To run it in sort
       mode pass it -s flag. No checks are performed then, it just sorts.

FILES
       /etc/group
	   Group account information.

       /etc/gshadow
	   Secure group account information.

       /etc/passwd
	   User account information.

SEE ALSO
       group(5), passwd(5), shadow(5), groupmod(8).

EXIT VALUES
       The grpck command exits with the following values:

       0
	   success

       1
	   invalid command syntax

       2
	   one or more bad group entries

       3
	   can't open group files

       4
	   can't lock group files

       5
	   can't update group files



System Management Commands	  10/28/2007			      GRPCK(8)