passwd

PASSWD(5)           Linux Programmer's Manual           PASSWD(5)


NAME
       passwd - password file

DESCRIPTION
       Passwd  is an ASCII file which contains a list of the sys-
       tem's users and the passwords they must  use  for  access.
       The  password  file  should  have  general read permission
       (many utilities, like ls(1) use it to map user IDs to user
       names), but write access only for the superuser.

       In  the good old days there was no great problem with this
       general  read  permission.   Everybody  could   read   the
       encrypted  passwords,  but  the  hardware  was too slow to
       crack a well-chosen  password,  and  moreover,  the  basic
       assumption  used  to be that of a friendly user-community.
       These days many people run  some  version  of  the  shadow
       password suite, where /etc/passwd has *'s instead of pass-
       words, and the  encrypted  passwords  are  in  /etc/shadow
       which is readable by root only.

       When  you  create  a  new  login, leave the password field
       empty and use passwd(1) to fill it.  A  star  (*)  in  the
       password  field  means  that  this  user can not login via
       login(1).

       There is one entry per line, and each line has the format:

              login_name:passwd:UID:GID:user_name:directory:shell

       The field descriptions are:


              login_name
                        the name of the user on the system.

              password  the encrypted optional user password.

              UID       the numerical user ID.

              GID       the numerical group ID for this user.

              user_name the (optional)  comment  field  (often  a
                        full user name).

              directory the user's $HOME directory.

              shell     the  program  to  run at login (if empty,
                        use /bin/sh).

NOTE
       If your root file system is on /dev/ram,   save  a
       changed  password  file  to  your  root file system floppy
       before you shut down  the  system  and  check  the  access
       rights.   If  you  want  to create user groups, their GIDs



Linux                      24 July 1993                         1





PASSWD(5)           Linux Programmer's Manual           PASSWD(5)


       must be equal and there must be an entry in /etc/group, or
       no group will exist.

FILES
       /etc/passwd

SEE ALSO
       passwd(1), login(1), group(5), shadow(5)

















































Linux                      24 July 1993                         2