shadow(4)
shadow --
shadow password file
Description
/etc/shadow
is an access-restricted ASCII system file
that contains an entry for each user on the system.
The fields within each entry are separated by colons;
each entry is separated from the next by a new-line.
Unlike the /etc/passwd file, /etc/shadow does
not have general read permission.
Here are the fields in /etc/shadow:
- ``login_name''
-
The name by which a user identifies himself or herself
when logging in.
- ``password''
-
A 13-character encrypted password for the user, a ``lock'' string
to indicate the login is not accessible, or no string to show
that there is no password for the login.
- ``lastchanged''
-
The number of days between January 1, 1970, and the date that the
password was last modified.
- ``minimum''
-
The minimum number of days required between password changes.
- ``maximum''
-
The maximum number of days the password is valid.
- ``warn''
-
The number of days before password expires that the user is warned.
- ``inactive''
-
The number of days of inactivity allowed for that user.
- ``expire''
-
An absolute date specifying when the login may no longer be used.
- ``flag''
-
A character identifying a password generator.
The encrypted password consists of 13 characters chosen from a 64-character
alphabet
(., /,
0-9, A-Z, a-z).
To update this file, use the passwd, useradd,
usermod, or userdel command.
Files
/etc/shadow
References
getspent(3G),
login(1),
passwd(1),
passwd(4),
putspent(3C),
useradd(1M),
userdel(1M),
usermod(1M)
30 January 1998
© 1998 The Santa Cruz Operation, Inc. All rights reserved.