linux - passwd (1)

       passwd, npasswd - change login password

       npasswd [ -P ] [ -V ] [ username ]

       Npasswd  changes or installs a login password for username
       (your own by default).  Only  the  super-user  can  change
       another users' password.

       When  changing  a  password,  npasswd  prompts for the old
       password and then for the new one.  The new password  must
       be typed twice to forestall mistakes.  The new password is
       checked for reasonableness.

       Npasswd accepts the option  switches  of  the  4.3BSD  and
       SunOS  4.X  passwd  but  impliments  none of them.  The -V
       option prints version and patch level information.

       The -P option indicates that npasswd  will  be  fed  input
       from  another program via a pipe.  This option is reserved
       for the super-user.

       Npasswd can change both local passwords and passwords in a
       Network Information Service (aka Yellow Pages) database.

       Npasswd will not accept passwords that:

              Are less than 6 characters long.

              Match  anything  in  your UNIX account information,
              such as your login name or an item from your  "fin-
              ger" data entry.

              Are found in the system's spelling dictionary.

              Have less than 5 different characters.

              Are entirely single case letters.

              Fail  any of these tests when reversed, pluralized,
              or truncated.

       /etc/passwd              System  password   file   to   be
       changed  /etc/opasswd             Backup  copy of previous
       passwd file /etc/ptmp           Lock file for  /etc/passwd
       /etc/npasswd.conf        Configuration  file  for  npasswd
       /usr/lib/npasswd/npasswd.help Help   file   for    npasswd
       /usr/lib/npasswd/npasswd.motd Message printed when npasswd
       is run

       passwd(1), passwd(5),  yppasswd(3R),  yppasswdd(8C),  fin-
       ger(1),  login(1), crypt(3), passwd.adjuct(5), ypfiles(5),
       ypmake(8)

       Various, hopefully self-explanitory.

       This program could do shells and  fullnames.   Probably  a
       future  version  will.  Since it tries to work for a range
       of UNIX systems, it will without doubt not  do  everything
       quite as well as the vendor-supplied version.

       Clyde Hoover
       Computation Center
       The University of Texas at Austin
       clyde@emx.utexas.edu, uunet!cs.utexas.edu!ut-emx!clyde