redhat man page for uuidgen

UUIDGEN(1)						      General Commands Manual							UUIDGEN(1)

NAME
       uuidgen - command-line utility to create a new UUID value

SYNOPSIS
       uuidgen [ -r | -t ]

DESCRIPTION
       The  uuidgen  program creates a new universally unique identifier (UUID) using the libuuid(3) library.  The new UUID can reasonably be con-
       sidered unique among all UUIDs created on the local system, and among UUIDs created on other systems in the past and in the future.

       There are two types of UUID's which uuidgen can generate: time-based UUID's and random-based UUID's.  By default 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 -r or -t options.

OPTIONS
       -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 /dev/random.

       -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.

RETURN VALUE
       The UUID of the form 1b4e28ba-2fa1-11d2-883f-b9a761bde3fb (in printf(3) format "%08x-%04x-%04x-%04x-%012x") is output to the standard  out-
       put.

CONFORMING TO
       OSF DCE 1.1

AUTHOR
       uuidgen was written by Andreas Dilger for libuuid.

AVAILABILITY
       uuidgen is part of libuuid from the e2fsprogs package and is available from http://e2fsprogs.sourceforge.net.

SEE ALSO
       libuuid(3)

E2fsprogs version 1.32						   November 2002							UUIDGEN(1)