1UUID(3) User Contributed Perl Documentation UUID(3)
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6 Data::UUID - Globally/Universally Unique Identifiers (GUIDs/UUIDs)
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9 The module Data::GUID provides another interface for generating GUIDs.
10 Right now, it relies on Data::UUID, but it may not in the future. Its
11 interface may be just a little more straightforward for the average
12 Perl programer.
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15 use Data::UUID;
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17 $ug = Data::UUID->new;
18 $uuid1 = $ug->create();
19 $uuid2 = $ug->create_from_name(<namespace>, <name>);
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21 $res = $ug->compare($uuid1, $uuid2);
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23 $str = $ug->to_string( $uuid );
24 $uuid = $ug->from_string( $str );
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27 This module provides a framework for generating v3 UUIDs (Universally
28 Unique Identifiers, also known as GUIDs (Globally Unique Identifiers).
29 A UUID is 128 bits long, and is guaranteed to be different from all
30 other UUIDs/GUIDs generated until 3400 CE.
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32 UUIDs were originally used in the Network Computing System (NCS) and
33 later in the Open Software Foundation's (OSF) Distributed Computing
34 Environment. Currently many different technologies rely on UUIDs to
35 provide unique identity for various software components. Microsoft
36 COM/DCOM for instance, uses GUIDs very extensively to uniquely identify
37 classes, applications and components across network-connected systems.
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39 The algorithm for UUID generation, used by this extension, is described
40 in the Internet Draft "UUIDs and GUIDs" by Paul J. Leach and Rich Salz.
41 (See RFC 4122.) It provides reasonably efficient and reliable
42 framework for generating UUIDs and supports fairly high allocation
43 rates -- 10 million per second per machine -- and therefore is suitable
44 for identifying both extremely short-lived and very persistent objects
45 on a given system as well as across the network.
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47 This modules provides several methods to create a UUID. In all
48 methods, "<namespace>" is a UUID and "<name>" is a free form string.
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50 # creates binary (16 byte long binary value) UUID.
51 $ug->create();
52 $ug->create_bin();
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54 # creates binary (16-byte long binary value) UUID based on particular
55 # namespace and name string.
56 $ug->create_from_name(<namespace>, <name>);
57 $ug->create_from_name_bin(<namespace>, <name>);
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59 # creates UUID string, using conventional UUID string format,
60 # such as: 4162F712-1DD2-11B2-B17E-C09EFE1DC403
61 # Note that digits A-F are capitalized, which is contrary to rfc4122
62 $ug->create_str();
63 $ug->create_from_name_str(<namespace>, <name>);
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65 # creates UUID string as a hex string,
66 # such as: 0x4162F7121DD211B2B17EC09EFE1DC403
67 # Note that digits A-F are capitalized, which is contrary to rfc4122
68 $ug->create_hex();
69 $ug->create_from_name_hex(<namespace>, <name>);
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71 # creates UUID string as a Base64-encoded string
72 $ug->create_b64();
73 $ug->create_from_name_b64(<namespace>, <name>);
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75 Binary UUIDs can be converted to printable strings using following methods:
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77 # convert to conventional string representation
78 $ug->to_string(<uuid>);
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80 # convert to hex string (using upper, rather than lower, case letters)
81 $ug->to_hexstring(<uuid>);
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83 # convert to Base64-encoded string
84 $ug->to_b64string(<uuid>);
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86 Conversely, string UUIDs can be converted back to binary form:
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88 # recreate binary UUID from string
89 $ug->from_string(<uuid>);
90 $ug->from_hexstring(<uuid>);
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92 # recreate binary UUID from Base64-encoded string
93 $ug->from_b64string(<uuid>);
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95 Finally, two binary UUIDs can be compared using the following method:
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97 # returns -1, 0 or 1 depending on whether uuid1 less
98 # than, equals to, or greater than uuid2
99 $ug->compare(<uuid1>, <uuid2>);
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101 Examples:
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103 use Data::UUID;
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105 # this creates a new UUID in string form, based on the standard namespace
106 # UUID NameSpace_URL and name "www.mycompany.com"
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108 $ug = Data::UUID->new;
109 print $ug->create_from_name_str(NameSpace_URL, "www.mycompany.com");
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111 EXPORT
112 The module allows exporting of several standard namespace UUIDs:
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114 NameSpace_DNS
115 NameSpace_URL
116 NameSpace_OID
117 NameSpace_X500
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120 Alexander Golomshtok <agolomsh@cpan.org>
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123 The Internet Draft "UUIDs and GUIDs" by Paul J. Leach and Rich Salz
124 (RFC 4122)
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128perl v5.34.0 2021-07-22 UUID(3)