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NAME | DESCRIPTION | FILES | SEE ALSO | COLOPHON |
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PASSWD(5) File Formats and Configuration PASSWD(5)
passwd - the password file
/etc/passwd contains one line for each user account, with seven
fields delimited by colons (“:”). These fields are:
• login name
• optional encrypted password
• numerical user ID
• numerical group ID
• user name or comment field
• user home directory
• optional user command interpreter
If the password field is a lower-case “x”, then the encrypted
password is actually stored in the shadow(5) file instead; there
must be a corresponding line in the /etc/shadow file, or else the
user account is invalid.
The encrypted password field may be empty, in which case no
password is required to authenticate as the specified login name.
However, some applications which read the /etc/passwd file may
decide not to permit any access at all if the password field is
blank.
A password field which starts with an exclamation mark means that
the password is locked. The remaining characters on the line
represent the password field before the password was locked.
Refer to crypt(3) for details on how this string is interpreted.
If the password field contains some string that is not a valid
result of crypt(3), for instance ! or *, the user will not be able
to use a unix password to log in (but the user may log in the
system by other means).
The comment field, also known as the gecos field, is used by
various system utilities, such as finger(1). The use of an
ampersand here will be replaced by the capitalised login name when
the field is used or displayed by such system utilities.
The home directory field provides the name of the initial working
directory. The login program uses this information to set the
value of the $HOME environmental variable.
The command interpreter field provides the name of the user's
command language interpreter, or the name of the initial program
to execute. The login program uses this information to set the
value of the $SHELL environmental variable. If this field is
empty, it defaults to the value /bin/sh.
/etc/passwd
User account information.
/etc/shadow
optional encrypted password file
/etc/passwd-
Backup file for /etc/passwd.
Note that this file is used by the tools of the shadow
toolsuite, but not by all user and password management tools.
crypt(3), getent(1), getpwnam(3), login(1), passwd(1), pwck(8),
pwconv(8), pwunconv(8), shadow(5), su(1), sulogin(8).
This page is part of the shadow-utils (utilities for managing
accounts and shadow password files) project. Information about
the project can be found at
⟨https://github.com/shadow-maint/shadow⟩. If you have a bug report
for this manual page, send it to
[email protected]. This page was obtained
from the project's upstream Git repository
⟨https://github.com/shadow-maint/shadow⟩ on 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2025-08-10.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
shadow-utils 4.18.0 08/11/2025 PASSWD(5)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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