PWCK(8) Maintenance Procedures PWCK(8)


pwck, grpck - password/group file checkers


/usr/sbin/pwck [filename]

/usr/sbin/grpck [filename]


pwck scans the password file and notes any inconsistencies. The checks
include validation of the number of fields, login name, user ID, group
ID, and whether the login directory and the program-to-use-as-shell
exist. The default password file is /etc/passwd.

grpck verifies all entries in the group file. This verification includes
a check of the number of fields, group name, group ID, whether any login
names belong to more than NGROUPS_MAX groups, and that all login names
appear in the password file. grpck also issues a warning if it finds an
entry (a single line) in the group file longer than 2047 characters.
Such an entry causes group maintenance commands, such as groupdel(8) and
groupmod(8), to fail.

The default group file is /etc/group.

All messages regarding inconsistent entries are placed on the stderr


o /etc/group

o /etc/passwd


getpwent(3C), group(5), passwd(5), attributes(7), groupdel(8),


Group entries in /etc/group with no login names are flagged.

Group file 'filename' is empty

The /etc/passwd or /etc/group file is an empty file.

cannot open file filename: No such file or directory

The /etc/passwd or /etc/group file does not exist.


If no filename argument is given, grpck checks the local group file,
/etc/group, and also makes sure that all login names encountered in the
checked group file are known to the system getpwent(3C) routine. This
means that the login names may be supplied by a network name service.

August 27, 2008 PWCK(8)