{ "content": [ { "type": "text", "text": "# uuidgen (man)\n\n## NAME\n\nuuidgen - create a new UUID value\n\n## SYNOPSIS\n\nuuidgen [options]\n\n## DESCRIPTION\n\nThe uuidgen program creates (and prints) a new universally unique identifier (UUID) using the\nlibuuid(3) library. The new UUID can reasonably be considered unique among all UUIDs created\non the local system, and among UUIDs created on other systems in the past and in the future.\n\n## TLDR\n\n> Generate unique identifiers (UUIDs).\n\n- Create a random UUIDv4:\n `uuidgen {{-r|--random}}`\n- Create a UUIDv1 based on the current time:\n `uuidgen {{-t|--time}}`\n- Create a UUIDv5 of the name with a specified namespace prefix:\n `uuidgen {{-s|--sha1}} {{-n|--namespace}} {{@dns|@url|@oid|@x500}} {{-N|--name}} {{object_name}}`\n\n*Source: tldr-pages*\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTION**\n- **OPTIONS** (9 subsections)\n- **CONFORMING TO**\n- **EXAMPLES**\n- **AUTHORS**\n- **SEE ALSO**\n- **REPORTING BUGS**\n- **AVAILABILITY**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n" } ], "structuredContent": { "command": "uuidgen", "section": "", "mode": "man", "summary": "uuidgen - create a new UUID value", "synopsis": "uuidgen [options]", "tldr_summary": "Generate unique identifiers (UUIDs).", "tldr_examples": [ { "description": "Create a random UUIDv4", "command": "uuidgen {{-r|--random}}" }, { "description": "Create a UUIDv1 based on the current time", "command": "uuidgen {{-t|--time}}" }, { "description": "Create a UUIDv5 of the name with a specified namespace prefix", "command": "uuidgen {{-s|--sha1}} {{-n|--namespace}} {{@dns|@url|@oid|@x500}} {{-N|--name}} {{object_name}}" } ], "tldr_source": "official", "flags": [ { "flag": "-r", "long": "--random", "arg": null, "description": "Generate a random-based UUID. This method creates a UUID consisting mostly of random bits. It requires that the operating system has a high quality random number generator, such as /dev/random." }, { "flag": "-t", "long": "--time", "arg": null, "description": "Generate a time-based UUID. This method creates a UUID based on the system clock plus the system’s ethernet hardware address, if present." }, { "flag": "-h", "long": "--help", "arg": null, "description": "Display help text and exit." }, { "flag": "-V", "long": "--version", "arg": null, "description": "Display version information and exit." }, { "flag": "-m", "long": "--md5", "arg": null, "description": "Use MD5 as the hash algorithm." }, { "flag": "-s", "long": "--sha1", "arg": null, "description": "Use SHA1 as the hash algorithm." }, { "flag": "-n", "long": "--namespace", "arg": null, "description": "Generate the hash with the namespace prefix. The namespace is UUID, or '@ns' where \"ns\" is well-known predefined UUID addressed by namespace name (see above)." }, { "flag": "-N", "long": "--name", "arg": null, "description": "Generate the hash of the name." }, { "flag": "-x", "long": "--hex", "arg": null, "description": "Interpret name name as a hexadecimal string." } ], "examples": [ "uuidgen --sha1 --namespace @dns --name \"www.example.com\"" ], "see_also": [ { "name": "libuuid", "section": "3", "url": "https://www.chedong.com/phpMan.php/man/libuuid/3/json" } ], "section_outline": [ { "name": "NAME", "lines": 2, "subsections": [] }, { "name": "SYNOPSIS", "lines": 2, "subsections": [] }, { "name": "DESCRIPTION", "lines": 19, "subsections": [] }, { "name": "OPTIONS", "lines": 1, "subsections": [ { "name": "-r --random", "lines": 4, "flag": "-r", "long": "--random" }, { "name": "-t --time", "lines": 3, "flag": "-t", "long": "--time" }, { "name": "-h --help", "lines": 2, "flag": "-h", "long": "--help" }, { "name": "-V --version", "lines": 2, "flag": "-V", "long": "--version" }, { "name": "-m --md5", "lines": 2, "flag": "-m", "long": "--md5" }, { "name": "-s --sha1", "lines": 2, "flag": "-s", "long": "--sha1" }, { "name": "-n --namespace", "lines": 3, "flag": "-n", "long": "--namespace" }, { "name": "-N --name", "lines": 2, "flag": "-N", "long": "--name" }, { "name": "-x --hex", "lines": 2, "flag": "-x", "long": "--hex" } ] }, { "name": "CONFORMING TO", "lines": 2, "subsections": [] }, { "name": "EXAMPLES", "lines": 2, "subsections": [] }, { "name": "AUTHORS", "lines": 2, "subsections": [] }, { "name": "SEE ALSO", "lines": 2, "subsections": [] }, { "name": "REPORTING BUGS", "lines": 2, "subsections": [] }, { "name": "AVAILABILITY", "lines": 6, "subsections": [] } ], "sections": { "NAME": { "content": "uuidgen - create a new UUID value\n", "subsections": [] }, "SYNOPSIS": { "content": "uuidgen [options]\n", "subsections": [] }, "DESCRIPTION": { "content": "The uuidgen program creates (and prints) a new universally unique identifier (UUID) using the\nlibuuid(3) library. The new UUID can reasonably be considered unique among all UUIDs created\non the local system, and among UUIDs created on other systems in the past and in the future.\n\nThere are three types of UUIDs which uuidgen can generate: time-based UUIDs, random-based\nUUIDs, and hash-based UUIDs. By default uuidgen will generate a random-based UUID if a\nhigh-quality random number generator is present. Otherwise, it will choose a time-based UUID.\nIt is possible to force the generation of one of these first two UUID types by using the\n--random or --time options.\n\nThe third type of UUID is generated with the --md5 or --sha1 options, followed by --namespace\nnamespace and --name name. The namespace may either be a well-known UUID, or else an alias to\none of the well-known UUIDs defined in RFC 4122, that is @dns, @url, @oid, or @x500. The name\nis an arbitrary string value. The generated UUID is the digest of the concatenation of the\nnamespace UUID and the name value, hashed with the MD5 or SHA1 algorithms. It is, therefore,\na predictable value which may be useful when UUIDs are being used as handles or nonces for\nmore complex values or values which shouldn’t be disclosed directly. See the RFC for more\ninformation.\n", "subsections": [] }, "OPTIONS": { "content": "", "subsections": [ { "name": "-r --random", "content": "Generate a random-based UUID. This method creates a UUID consisting mostly of random\nbits. It requires that the operating system has a high quality random number generator,\nsuch as /dev/random.\n", "flag": "-r", "long": "--random" }, { "name": "-t --time", "content": "Generate a time-based UUID. This method creates a UUID based on the system clock plus the\nsystem’s ethernet hardware address, if present.\n", "flag": "-t", "long": "--time" }, { "name": "-h --help", "content": "Display help text and exit.\n", "flag": "-h", "long": "--help" }, { "name": "-V --version", "content": "Display version information and exit.\n", "flag": "-V", "long": "--version" }, { "name": "-m --md5", "content": "Use MD5 as the hash algorithm.\n", "flag": "-m", "long": "--md5" }, { "name": "-s --sha1", "content": "Use SHA1 as the hash algorithm.\n", "flag": "-s", "long": "--sha1" }, { "name": "-n --namespace", "content": "Generate the hash with the namespace prefix. The namespace is UUID, or '@ns' where \"ns\"\nis well-known predefined UUID addressed by namespace name (see above).\n", "flag": "-n", "long": "--namespace" }, { "name": "-N --name", "content": "Generate the hash of the name.\n", "flag": "-N", "long": "--name" }, { "name": "-x --hex", "content": "Interpret name name as a hexadecimal string.\n", "flag": "-x", "long": "--hex" } ] }, "CONFORMING TO": { "content": "OSF DCE 1.1\n", "subsections": [] }, "EXAMPLES": { "content": "uuidgen --sha1 --namespace @dns --name \"www.example.com\"\n", "subsections": [] }, "AUTHORS": { "content": "uuidgen was written by Andreas Dilger for libuuid(3).\n", "subsections": [] }, "SEE ALSO": { "content": "libuuid(3), RFC 4122 \n", "subsections": [] }, "REPORTING BUGS": { "content": "For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.\n", "subsections": [] }, "AVAILABILITY": { "content": "The uuidgen command is part of the util-linux package which can be downloaded from Linux\nKernel Archive .\n\n\n\nutil-linux 2.37.2 2021-06-02 UUIDGEN(1)", "subsections": [] } } } }