1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
= uuid(1)
== NAME
uuid - generate a UUID version 4 or 7, or validate a UUID string.
== SYNOPSYS
*uuid* [-v (4|7)] *uuid* [_STRING_]
== EXAMPLES
=== Print a (version 4) UUID on the terminal
[source, sh]
....
$ uuid
d3891787-c952-af17-d697-0df3b85981e1
....
=== Print a verson 7 UUID on the terminal
[source, sh]
....
$ uuid -v 7
d3891787-c952-af17-d697-0df3b85981e1
....
=== Create a new UUID as part of a path
[source, sh]
....
dir="$PWD"/"$(uuid)"/data
....
=== Validate a given UUID
[source, sh]
....
ID="$(basename -- "$directory")"
if ! uuid "$ID"; then
echo "Bad UUID in directory: $ID" >&2
exit 1
fi
....
== DESCRIPTION
The *uuid* utility generates a new UUID when no _STRING_ is given and write it to _stdout_. If a _STRING_ is given, *uuid* validates it and exits, and produces no output.
The *-v* option allows for choosing which type of UUID to be emitted, either version 4 ("the random one") or version 7 ("the sortable one"). When omitted, version 4 is chosen as default.
== OPTIONS
*-v NUMBER*:: Choose the UUID version *NUMBER* to be generated. Supported values are 4 (the default) and 7.
== OPERANDS
_STRING_:: If it is
*not given*::: generate a brand new random UUIDv4, print it to _stdout_ and exit normally;
*given*::: test if it is a valid UUIDv4 and exit normally if so.
== IO
=== STDIN
Not used.
=== STDOUT
The UUIDv4 format is made of byte blocks encoded as hexadecimals, using a <hyphen-minus>('`-`') as the block separator:
[source, sh]
....
XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
....
An example output is:
[source, sh]
....
cb46d0c0-b2aa-4a6c-a119-8deace2544a2
....
=== STDERR
Errors on UUID validation are sent to the standard error. For instance:
[source, sh]
....
$ uuid not-a-uuid-123 1>/dev/null
uuid: str isn't of the correct length
....
When valid, validation emits nothing and exits with 0.
=== INPUT FILES
None.
=== OUTPUT FILES
None.
== EXIT STATUS
0:: Generating or validating a UUID was successfull.
3:: UUID validation failed.
== CONFORMING TO
The versions 4 and 7 of the UUID defined in *RFC 9562*.
== SEE ALSO
== AUTHORS
mailto:eu@euandre.org[EuAndreh] and contributors.
== BUGS
* Report bugs to the mailto:~euandreh/public-inbox@lists.sr.ht[mailing list]. Use the subject "[uuid] BUG or TASK: <description>".
* Browse bugs https://euandre.org/git/uuid/TODOs.html[online].
* https://euandre.org/git/uuid/[Homepage].
* https://lists.sr.ht/~euandreh/public-inbox?search=%5Buuid%5D[Comments and discussions].
|
