.\" Copyright 1999 Andreas Dilger (adilger@enel.ucalgary.ca)
.\"
.\" This man page was created for libuuid.so.1.1 from e2fsprogs-1.14.
.\"
.\" This file may be copied under the terms of the GNU Public License.
.\"
.\" Created  Wed Mar 10 17:42:12 1999, Andreas Dilger
.TH UUIDGEN 1 "May 2009" "Linux"
.SH NAME
uuidgen \- command\-line utility to create a new UUID value
.SH SYNOPSIS
.B uuidgen
.RB [ \-r | \-t ]
.SH DESCRIPTION
The
.B uuidgen
program creates (and prints)
a new universally unique identifier (UUID) using the
.BR libuuid (3)
library.  The new UUID can reasonably be considered unique among
all UUIDs created on the local system,
and among UUIDs created on other systems in the past
and in the future.
.PP
There are two types of UUID's which
.B uuidgen
can generate: time-based UUID's and random-based UUID's.  By
default
.B uuidgen
will generate a random-based UUID if a high-quality random number
generator is present.  Otherwise, it will chose a time-based UUID.  It
is possible to force the generation of one of these two
UUID types by using the
.B \-r
or
.B \-t
options.
.SH OPTIONS
.TP
.B \-r
Generate a random-based UUID.  This method creates a UUID consisting mostly
of random bits.  It requires that the operating system have a high
quality random number generator, such as
.IR /dev/random .
.TP
.B \-t
Generate a time-based UUID.  This method creates a UUID based on the system
clock plus the system's ethernet hardware address, if present.
.SH "CONFORMING TO"
OSF DCE 1.1
.SH AUTHOR
.B uuidgen
was written by Andreas Dilger for libuuid.
.SH AVAILABILITY
The uuidgen command is part of the util-linux-ng package and is available from
ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.
.SH "SEE ALSO"
.BR libuuid (3)