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

   The encrypted password field may be blank, 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. 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. If the password
   field is any other string, then it will be treated as an encrypted
   password, as specified by crypt(3).

   The comment field is used by various system utilities, such as

   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.


       User account information.

       optional encrypted password file

       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).


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