passwd(1)                                               passwd(1)



NAME
     passwd - changes the login password

SYNOPSIS
     passwd [name]

ARGUMENTS
     name Specifies the login name of the user.

DESCRIPTION
     This command changes (or installs) a password associated
     with the login name.

     Ordinary users may change only the password that corresponds
     to their login name.

     The passwd program prompts ordinary users for their old
     password, if any.  It then prompts for the new password
     twice.  The first time the new password is entered, passwd
     checks to see if the old password has aged sufficiently.  If
     aging is insufficient, the new password is rejected and
     passwd terminates; see passwd(4).

     Assuming aging is sufficient, a check is made to ensure that
     the new password meets construction requirements. When the
     new password is entered a second time, the two copies of the
     new password are compared.  If the two copies are not
     identical, the cycle of prompting for the new password is
     repeated for at most two more times.

     Passwords must meet the following requirements:

          Each password must have at least six characters.  Only
          the first eight characters are significant.

          Each password must contain at least two alphabetic
          characters (uppercase or lowercase) and at least one
          numeric or special character.

          Each password must differ from the user's login name
          and any reverse or circular shift of that login name.
          For comparison purposes, an uppercase letter and its
          corresponding lowercase letter are equivalent.

          New passwords must differ from the old by at least
          three characters.  For comparison purposes, an
          uppercase letter and its corresponding lowercase letter
          are equivalent.

     One whose effective user ID is zero is called a superuser;
     see id(1), and su(1).  Superusers may change any password;
     hence, passwd does not prompt superusers for the old



January 1992                                                    1

passwd(1)                                               passwd(1)



     password.  Superusers are not forced to comply with password
     aging and password construction requirements.  A superuser
     can create a null password by entering a carriage return in
     response to the prompt for a new password.

EXAMPLES
     Entering:

        passwd

     will give the response

        Changing password for <username>

     and will then prompt for your present password and for the
     new password (twice).

FILES
     /bin/passwd
          Executable file
     /etc/passwd
          Executable file

SEE ALSO
     chsh(1), login(1), id(1), su(1)

     crypt(3C), passwd(4) in A/UX Programmer's Reference




























2                                                    January 1992