GRPCK(1)                                                                                 GRPCK(1)



NAME
       grpck - verify integrity of group files

SYNOPSIS
       grpck [-r] [group shadow]

DESCRIPTION
       grpck 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 for-
       matted or which have other incorrectable errors.

       Checks are made to verify that each entry has

            - the correct number of fields
            - a unique group name
            - 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  com-
       mand 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 - encrypted passwords and group administrator information
       /etc/passwd - user information

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

DIAGNOSTICS
       The grpck command exits with the following values:

       0    Success

       1    Syntax Error

       2    One or more bad group entries

       3    Cannot open group files

       4    Cannot lock group files

       5    Cannot update group files

AUTHOR
       Julianne Frances Haugh ()



                                                                                         GRPCK(1)