|  | .\" Copyright 1999 Andreas Dilger (adilger@enel.ucalgary.ca) | 
|  | .\" | 
|  | .\" This file may be copied under the terms of the GNU Public License. | 
|  | .TH UUIDGEN 1 "June 2011" "util-linux" "User Commands" | 
|  | .SH NAME | 
|  | uuidgen \- create a new UUID value | 
|  | .SH SYNOPSIS | 
|  | .B uuidgen | 
|  | [options] | 
|  | .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 UUIDs which | 
|  | .B uuidgen | 
|  | can generate: time-based UUIDs and random-based UUIDs.  By default | 
|  | .B uuidgen | 
|  | will generate a random-based UUID if a high-quality random number | 
|  | generator is present.  Otherwise, it will choose 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 | 
|  | .BR \-r , " \-\-random" | 
|  | 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 | 
|  | .BR \-t , " \-\-time" | 
|  | Generate a time-based UUID.  This method creates a UUID based on the system | 
|  | clock plus the system's ethernet hardware address, if present. | 
|  | .TP | 
|  | .BR \-h , " \-\-help" | 
|  | Display help text and exit. | 
|  | .TP | 
|  | .BR \-V , " \-\-version" | 
|  | Display version information and exit. | 
|  | .SH "CONFORMING TO" | 
|  | OSF DCE 1.1 | 
|  | .SH AUTHOR | 
|  | .B uuidgen | 
|  | was written by Andreas Dilger for libuuid. | 
|  | .SH SEE ALSO | 
|  | .BR libuuid (3) | 
|  | .SH AVAILABILITY | 
|  | The uuidgen command is part of the util-linux package and is available from | 
|  | ftp://ftp.kernel.org/pub/linux/utils/util-linux/. |