MKPASSWD(1) General Commands Manual MKPASSWD(1)

# [NAME](#NAME)

mkpasswd - generate new password, optionally apply it to a user

# [SYNOPSIS](#SYNOPSIS)

**mkpasswd** *\[* *args* ] \[ *user* ]

# [INTRODUCTION](#INTRODUCTION)

**mkpasswd** generates passwords and can apply them automatically to users. mkpasswd is based on the code from Chapter 23 of the O'Reilly book "Exploring Expect".

# [USAGE](#USAGE)

With no arguments, **mkpasswd** returns a new password.

mkpasswd

With a user name, **mkpasswd** assigns a new password to the user.

mkpasswd don

The passwords are randomly generated according to the flags below.

# [FLAGS](#FLAGS)

The **-l** flag defines the length of the password. The default is 9. The following example creates a 20 character password.

mkpasswd -l 20

The **-d** flag defines the number of digits that must be in the password. The default is 2. The following example creates a password with 3 digits.

mkpasswd -d 3

The **-c** flag defines the minimum number of lowercase alphabetic characters that must be in the password. The default is 2.

The **-C** flag defines the number of uppercase alphabetic characters that must be in the password. The default is 2.

The **-s** flag defines the number of special characters that must be in the password. The default is 1.

The **-p** flag names a program to set the password. By default, /etc/yppasswd is used if present, otherwise /bin/passwd is used.

The **-2** flag causes characters to be chosen so that they alternate between right and left hands (qwerty-style), making it harder for anyone watching passwords being entered. This can also make it easier for a password-guessing program.

The **-v** flag causes the password-setting interaction to be visible. By default, it is suppressed.

# [EXAMPLE](#EXAMPLE)

The following example creates a 15-character password that contains 3 digits and 5 uppercase characters.

mkpasswd -l 15 -d 3 -C 5

# [SEE ALSO](#SEE_ALSO)

*"Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Programs"* by Don Libes, O'Reilly and Associates, January 1995.

# [AUTHOR](#AUTHOR)

Don Libes, National Institute of Standards and Technology

**mkpasswd** is in the public domain. NIST and I would appreciate credit if this program or parts of it are used.

22 August 1994

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Document: mkpasswd(1) from expect 6.0_alpha2-r0 (Chainguard OS)