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UUIDGEN(1)		    General Commands Manual		    UUIDGEN(1)

NAME
       uuidgen -- generate universally unique identifiers

SYNOPSIS
       uuidgen [-1cr] [-n count] [-o filename]

DESCRIPTION
       The uuidgen utility by default generates	a single DCE version 1 univer-
       sally unique identifier (UUID), also known as a globally	unique identi-
       fier  (GUID).  The UUID is written to stdout by default.	 The following
       options can be used to change the behaviour of uuidgen:

       -1      This option only	has effect if multiple identifiers are	to  be
	       generated  and instructs	uuidgen	to not generate	them in	batch,
	       but one at a time.

       -c      This option controls creation of	compact	UUID (without hyphen).

       -n      This option controls the	number of identifiers  generated.   By
	       default,	 multiple identifiers are generated in batch.  The up-
	       per hard	limit is 2048 (see uuidgen(2)).

       -o      Redirect	output to filename instead of stdout.

       -r      This option controls creation of	random UUID (version 4).

       Batched generation yields a dense set of	identifiers in such a way that
       there is	no identifier that is larger than the smallest	identifier  in
       the  set	and smaller than the largest identifier	in the set and that is
       not already in the set.

       When generating the identifiers one at a	time, the identifiers will  be
       close  to  each other, but operating system latency and processing time
       will be reflected in the	distance between two successive	identifiers.

EXIT STATUS
       The uuidgen utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
       Generate	a batch	of three UUIDs.	 Notice	the similarity of  the	string
       before the first	hyphen of the UUID (known as time_low in rfc4122):

	     $ uuidgen -n3
	     8bc44345-4d90-11ee-88c7-b42e991fc52e
	     8bc44346-4d90-11ee-88c7-b42e991fc52e
	     8bc44347-4d90-11ee-88c7-b42e991fc52e

       Generate	a batch	of random UUIDs	without	hyphens:

	     $ uuidgen -r -c -n3
	     5ad8b60a0f4e41f59c82d273202275f9
	     6c41925486cd4bf59720a5bad85de2e4
	     8144fdab63f648a1812d12453f975313

       Notice that the UUIDs are not similar to	each other.

SEE ALSO
       uuidgen(2), uuid(3)

HISTORY
       The uuidgen command first appeared in FreeBSD 5.0.

FreeBSD	15.0			August 27, 2025			    UUIDGEN(1)

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