UUID(1)

NAME
OSSP uuid - Universally Unique Identifier Command-Line Tool

VERSION
OSSP uuid .1.0 (16-Feb-2004)

SYNOPSIS
uuid [-v version] [-m] [-n count] [-1] [-r] [-o filename] [namespace name]

uuid -d [-r] [-o filename] uuid

DESCRIPTION
OSSP uuid is a ISO-C application programming interface (API) and corresponding command line interface (CLI) for the generation of DCE 1.1 and ISO/IEC 11578:1996 compliant Universally Unique Identifier (UUID). It supports DCE 1.1 variant UUIDs of version 1 (time and node based), version 3 (name based) and version 4 (random number based).

UUIDs are 128 bit numbers which are intended to have a high likelihood of uniqueness over space and time and are computationally difficult to guess. They are globally unique identifiers which can be locally generated without contacting a global registration authority. UUIDs are intended as unique identifiers for both mass tagging objects with an extremely short lifetime and to reliably identifying very persistent objects across a network.

This is the command line interface (CLI) of OSSP uuid. For a detailed description of UUIDs see the documentation of the application programming interface (API) in uuid(3).

OPTIONS

-v version
    Sets the version of the generated DCE 1.1 variant UUID. Supported are version "1", "3" and "4". The default is "1".

    For version 3 UUIDs the additional command line arguments namespace and name have to be given. The namespace is either a UUID in string representation or an identifier for internally pre-defined namespace UUIDs (currently known are "ns:DNS", "ns:URL", "ns:OID", and "ns:X500"). The name is a string of arbitrary length.

-m  Forces the use of a random multi-cast MAC address when generating version 1 UUIDs. By default the real physical MAC address of the system is used.

-n count
    Generate count UUIDs instead of just a single one (the default).

-1  If option -n is used with a count greater than 1, then this option can enforce the reset the UUID context for each generated UUID. This makes no difference for version 3 and 4 UUIDs. But version 1 UUIDs are based on the previously generated UUID which is remembered in the UUID context of the API. Option -1 deletes the remembered UUID on each iteration.

-r  Output the generated UUID in 128 bit (network byte order) raw binary representation format. The default is to output the generated UUID in the standardized ASCII string representation.

-o filename
    Write output to filename instead of to stdout.

-d  Decode a given UUID (given as a command line argument or if the command line argument is "-" the UUID is read from stdin) and dump textual information about the UUID.

EXAMPLES
 # generate DCE 1.1 v1 UUID (time and node based)
 $ uuid -v1
 01c47915-4777-11d8-bc70-0090272ff725

 # decode and dump DCE 1.1 v1 UUID (time and node based)
 $ uuid -d 01c47915-4777-11d8-bc70-0090272ff725
 UUID:    01c47915-4777-11d8-bc70-0090272ff725
 variant: DCE 1.1, ISO/IEC 11578:1996
 version: 1 (time and node based)
 content: time:  2004-01-15 16:22:26.376322.1 UTC
          clock: 15472 (usually random)
          node:  00:90:27:2f:f7:25 (global unicast)

 # generate DCE 1.1 v3 UUID (name based)
 $ uuid -v3 ns:URL http://www.ossp.org/
 02d9e6d5-9467-382e-8f9b-9300a64ac3cd

 # decode and dump DCE 1.1 v3 UUID (name based)
 $ uuid -d 02d9e6d5-9467-382e-8f9b-9300a64ac3cd
 UUID:    02d9e6d5-9467-382e-8f9b-9300a64ac3cd
 variant: DCE 1.1, ISO/IEC 11578:1996
 version: 3 (name based)
 content: 02:D9:E6:D5:94:67:08:2E:0F:9B:93:00:A6:4A:C3:CD
          (not decipherable, because message digest only)

 # generate DCE 1.1 v4 UUID 4 (random data based)
 $ uuid -v4
 eb424026-6f54-4ef8-a4d0-bb658a1fc6cf

 # decode and dump DCE 1.1 v4 UUID 4 (random data based)
 $ uuid -d eb424026-6f54-4ef8-a4d0-bb658a1fc6cf
 UUID:    eb424026-6f54-4ef8-a4d0-bb658a1fc6cf
 variant: DCE 1.1, ISO/IEC 11578:1996
 version: 4 (random data based)
 content: EB:42:40:26:6F:54:0E:F8:24:D0:BB:65:8A:1F:C6:CF
          (no semantics, because random data only)

SEE ALSO
uuid(3).