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32 .Nd generate universally unique identifiers
41 utility by default generates a single DCE version 1
42 universally unique identifier (UUID),
43 also known as a globally unique identifier (GUID).
44 The UUID is written to stdout by default.
45 The following options can be used to change the behaviour of
47 .Bl -tag -width indent
49 This option only has effect if multiple identifiers are to be generated and
52 to not generate them in batch, but one at a time.
54 This option controls the number of identifiers generated.
56 identifiers are generated in batch.
63 Batched generation yields a dense set of identifiers in such a way that there
64 is no identifier that is larger than the smallest identifier in the set and
65 smaller than the largest identifier in the set and that is not already in the
68 When generating the identifiers one at a time, the identifiers will be close
69 to each other, but operating system latency and processing time will be
70 reflected in the distance between two successive identifiers.
79 command first appeared in