NAME

passwd − password file

DESCRIPTION

The passwd file contains for each user the following information:

name (login name)
encrypted password
numerical user ID
numerical group ID
user’s real name, office, extension, home phone.
initial working directory
program to use as Shell

The ‘user’s real name’ may contain an amperstand (&), meaning insert the login name.  This information is set by the chfn() command and used by the finger() command.

This is an ASCII file.  Each field within a user entry is separated from the next by a colon.  Each user 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 /bin/sh is used.

This file resides in directory /etc. Because of the encrypted passwords, it has general read permission and can be used, for example, to map numerical user IDs to names.

Appropriate precautions must be taken to lock the file against changes if it is to be edited with a text editor.  The vipw command does the necessary locking.

RESTRICTIONS

The ‘name’ may contain only lower case ASCII characters a to z and the numbers 0 to 9. 

FILES

/etc/passwd

SEE ALSO

chfn(1), finger(1), login(1), passwd(1), crypt(3), getpwent(3), group(5), adduser(8), vipw(8)

File Formats