Uuid

uuid_nil¶

Return the RFC4122 nil UUID (all zeros).

Exit codes¶

• 0: Always

Output on stdout¶

• 00000000-0000-0000-0000-000000000000

uuid_v1¶

Generate a version 1 (time-based, MAC address) UUID. Uses uuidgen --time if available, otherwise generates from scratch.

Exit codes¶

• 0: Always

Output on stdout¶

• A version 1 UUID string

uuid_v2¶

Generate a version 2 (DCE Security) UUID. UUIDv2 is not implemented. The DCE Security UUID specification was never made public, implementations are incompatible, and the format is effectively defunct. Use uuid_v1 for time-based UUIDs or uuid_v4 for random UUIDs.

Exit codes¶

• 1: Always

uuid_v3¶

Generate a version 3 (MD5 namespace-based) UUID. Alias for: uuid_hash v3 namespace name

Arguments¶

• $1 (string): Namespace: @dns, @url, @oid, @x500, or @custom
• $2 (string): Name

Exit codes¶

• 0: Success
• 1: Missing namespace or name

Output on stdout¶

• A version 3 UUID string

uuid_v4¶

Generate a version 4 (fully random) UUID. Uses uuidgen --random, /proc/sys/kernel/random/uuid, or a bash-native fallback.

Exit codes¶

• 0: Always

Output on stdout¶

• A version 4 UUID string

uuid_v5¶

Generate a version 5 (SHA-1 namespace-based) UUID. Alias for: uuid_hash v5 namespace name

Arguments¶

• $1 (string): Namespace: @dns, @url, @oid, @x500, or @custom
• $2 (string): Name

Exit codes¶

• 0: Success
• 1: Missing namespace or name

Output on stdout¶

• A version 5 UUID string

uuid_v6¶

Generate a version 6 (reordered time) UUID. Functionally equivalent to v1 but with timestamp bits stored MSB-first, making v6 UUIDs lexicographically sortable. Prefer v6 over v1 for new work.

Exit codes¶

• 0: Always

Output on stdout¶

• A version 6 UUID string

uuid_v7¶

Generate a version 7 (Unix timestamp + random) UUID. Uses a 48-bit millisecond Unix timestamp followed by random bits, making v7 UUIDs lexicographically sortable without requiring a MAC address. Prefer v7 over v1/v6 for new work that doesn't need Gregorian-epoch time.

Exit codes¶

• 0: Always

Output on stdout¶

• A version 7 UUID string

uuid_v8¶

Generate a version 8 (custom) UUID. RFC 9562 mandates only the version and variant bits; the three custom fields (custom_a 48-bit, custom_b 12-bit, custom_c 62-bit) are implementation-defined. This implementation fills them with random data by default, producing a UUID that is distinguishable from v4 by version number. Callers with a specific encoding scheme can supply their own hex values for each field; any omitted field is randomised.

Options¶

• --custom-a

hex 48-bit custom field (up to 12 hex chars)

• --custom-b

hex 12-bit custom field (up to 3 hex chars)

• --custom-c

hex 62-bit custom field (up to 15 hex chars)

Exit codes¶

• 0: Success
• 1: Invalid arguments

Output on stdout¶

• A version 8 UUID string

uuid_pseudo¶

Generate a pseudo-UUID using od and /dev/urandom. Not RFC4122 compliant; useful for quick non-critical identifiers.

Exit codes¶

• 0: Always

Output on stdout¶

• A pseudo-UUID string

uuid_gen¶

Generate a UUID of the specified version (default: v4).

Arguments¶

• $1 (string): Optional: -0/-nil/-null, -1/--time, -2, -3/--md5, -4/-r/--random,

Exit codes¶

• 0: Success
• 1: Invalid arguments or unsupported version

Output on stdout¶

• A UUID string

uuid_switch_endian¶

Blindly convert a UUID between little-endian and mixed-endian (Microsoft) byte order. The first three octets are byte-swapped; the remainder are unchanged.

Arguments¶

• $1 (string): A valid UUID string

Exit codes¶

• 0: Success
• 1: No UUID supplied or invalid UUID structure/content

Output on stdout¶

• UUID with first three octets in reversed byte order

validate_uuid¶

Validate that a string is a structurally and content-valid UUID. Checks the 8-4-4-4-12 structure and that all characters are hexadecimal.

Arguments¶

• $1 (string): The UUID string to validate

Exit codes¶

• 0: Valid UUID
• 1: Invalid structure or non-hex characters found