passwd(5)passwd(5)Namepasswd - password file
Description
The file is an ASCII file that contains the following information for
each user:
Login name
Password field
User ID
Group ID
User's real name, office, extension, home phone
Initial working directory
Program to use as Shell
Each line in the file represents a user entry. Each field within a
user entry is separated from the next by a colon. Each user entry is
separated from the next by a new line. If the password field is null,
no password is demanded; if the Shell field is null, then is used.
This file resides in directory Because the password, if present, is
encrypted, the file has general read permission and can be used, for
example, to map user IDs to names.
The ``user's real name'' can contain an ampersand (&), meaning insert
the login name. This information is set by the command and used by the
command.
Appropriate precautions must be taken to lock the file against changes
if it is to be edited with a text editor. The command does the neces‐
sary locking.
If the system is running UPGRADE security level and an asterisk appears
in the password field, or if the system is running ENHANCED level, then
the content of the password field is ignored and the password for the
account is located in the authentication database. See and the Security
Guide for Administrators for more information.
The files and if they exist, contain the hashed version of the file.
If present, they are used by the and functions to retrieve entries
rapidly. See for more information.
The database can be distributed in a network by a naming service, such
as Yellow Pages or BIND/Hesiod. See the Guide to the Yellow Pages Ser‐
vice or the Guide to the BIND/Hesiod Service for setup information.
Restrictions
The ``name'' can contain only lowercase ASCII characters a to z and the
numbers 0 to 9.
FilesSee Alsochfn(1), finger(1), login(1), passwd(1), crypt(3), getpwent(3),
auth(5), group(5), adduser(8), mkpasswd(8), vipw(8)
Guide to the BIND/Hesiod Service
Guide to the Yellow Pages Service
Security Guide for Administrators
passwd(5)