The uuidgen program creates (and prints) a new universally unique
identifier (UUID) using the 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
There are two types of UUIDs which uuidgen can generate: time-based
UUIDs and random-based UUIDs. By default 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 -r or -t options.
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.
Generate a time-based UUID. This method creates a UUID based
on the system clock plus the system's ethernet hardware
address, if present.
Display help text and exit.
Display version information and exit.
This page is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
bug report for this manual page, send it to
email@example.com. This page was obtained from the
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2017-03-13. If you discover any rendering problems in this HTML ver‐
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information in this COLOPHON (which is not part of the original man‐
ual page), send a mail to firstname.lastname@example.org
util-linux June 2011 UUIDGEN(1)