.\" Copyright 1992 - 1993, Julianne Frances Haugh
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.\"	$Id: grpck.8,v 1.5 2000/08/26 18:27:17 marekm Exp $
.\"
.TH GRPCK 1
.SH NAME
grpck \- verify integrity of group files
.SH SYNOPSIS
\fBgrpck\fR [\fB-r\fR] [\fIgroup\fR \fIshadow\fR]
.SH DESCRIPTION
\fBgrpck\fR verifies the integrity of the system authentication information.
All entries in the \fI/etc/group\fR and \fI/etc/gshadow\fR 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 incorrectable errors.
.P
Checks are made to verify that each entry has
.sp
.in +.5i
- the correct number of fields
.br
- a unique group name
.br
- a valid list of members and administrators
.in -.5i
.sp
.P
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
\fBgroupmod\fR command to correct the error.
.P
The commands which operate on the \fI/etc/group\fR file are not able to
alter corrupted or duplicated entries.
\fBgrpck\fR should be used in those circumstances to remove the offending
entry.
.SH OPTIONS
By default, \fBgrpck\fR operates on the files \fI/etc/group\fR and
\fI/etc/gshadow\fR.
The user may select alternate files with the \fIgroup\fR and \fIshadow\fR
parameters.
Additionally, the user may execute the command in read-only mode by
specifying the \fB-r\fR flag.
This causes all questions regarding changes to be answered \fBno\fR
without user intervention.
.SH FILES
/etc/group \- group account information
.br
/etc/gshadow \- encrypted passwords and group administrator information
.br
/etc/passwd \- user information
.SH SEE ALSO
.BR groupmod (8),
.BR group (5),
.BR passwd (5),
.BR shadow (5)
.SH DIAGNOSTICS
The \fBgrpck\fR command exits with the following values:
.IP 0 5
Success
.IP 1 5
Syntax Error
.IP 2 5
One or more bad group entries
.IP 3 5
Cannot open group files
.IP 4 5
Cannot lock group files
.IP 5 5
Cannot update group files
.SH AUTHOR
Julianne Frances Haugh (jfh@austin.ibm.com)