1UUIDGEN(1) General Commands Manual UUIDGEN(1)
2
3
4
6 uuidgen - command-line utility to create a new UUID value
7
9 uuidgen [ -r | -t ]
10
12 The uuidgen program creates a new universally unique identifier (UUID)
13 using the libuuid(3) library. The new UUID can reasonably be consid‐
14 ered unique among all UUIDs created on the local system, and among
15 UUIDs created on other systems in the past and in the future.
16
17 There are two types of UUID's which uuidgen can generate: time-based
18 UUID's and random-based UUID's. By default uuidgen will generate a
19 random-based UUID if a high-quality random number generator is present.
20 Otherwise, it will chose a time-based UUID. It is possible to force
21 the generation of one of these two UUID types by using the
22
23 A UUID of the form 1b4e28ba-2fa1-11d2-883f-b9a761bde3fb (in printf(3)
24 format "%08x-%04x-%04x-%04x-%012x") is output to the standard output.
25 -r or -t options.
26
28 -r Generate a random-based UUID. This method creates a UUID con‐
29 sisting mostly of random bits. It requires that the operating
30 system have a high quality random number generator, such as
31 /dev/random.
32
33 -t Generate a time-based UUID. This method creates a UUID based on
34 the system clock plus the system's ethernet hardware address, if
35 present.
36
38 OSF DCE 1.1
39
41 uuidgen was written by Andreas Dilger for libuuid.
42
44 uuidgen is part of libuuid from the e2fsprogs package and is available
45 from http://e2fsprogs.sourceforge.net.
46
48 libuuid(3)
49
50
51
52E2fsprogs version 1.40.2 July 2007 UUIDGEN(1)