.\" Copyright (c) 1988 The Regents of the University of California.
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.\"	@(#)passwd.1	6.5 (Berkeley) 2/22/89
.\"
.TH PASSWD 1 "February 22, 1989"
.UC 4
.SH NAME
passwd \- change password file information
.SH SYNOPSIS
.B passwd
[ user ]
.SH DESCRIPTION
.I Passwd
changes the user's password.  First, the user is prompted for their old
password, and then, if that is correct, for the new password.  The new
password must be entered twice to forestall any typing errors.  The
super-user is not prompted for the old password.
.PP
Once the password has been verified,
.I passwd
uses
.IR mkpasswd (8)
to update the user database.  This is run in the background, and,
at very large sites could take several minutes.  Until this update
is completed, the password file is unavailable for other updates
and the new password will not be available to programs.
.SH FILES
.DT
/etc/master.passwd		the user database
.RE
.SH "SEE ALSO"
chpass(1), login(1), passwd(5), mkpasswd(8), vipw(8)
.br
Robert Morris and Ken Thompson,
.I UNIX password security