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Diffstat (limited to 'contrib/uuid-ossp/README.uuid-ossp')
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diff --git a/contrib/uuid-ossp/README.uuid-ossp b/contrib/uuid-ossp/README.uuid-ossp deleted file mode 100644 index 6c5b0d04ed..0000000000 --- a/contrib/uuid-ossp/README.uuid-ossp +++ /dev/null @@ -1,97 +0,0 @@ -UUID Generation Functions -========================= -Peter Eisentraut <peter_e@gmx.net> - -This module provides functions to generate universally unique -identifiers (UUIDs) using one of the several standard algorithms, as -well as functions to produce certain special UUID constants. - - -Installation ------------- - -The extra library required can be found at -<http://www.ossp.org/pkg/lib/uuid/>. - - -UUID Generation ---------------- - -The relevant standards ITU-T Rec. X.667, ISO/IEC 9834-8:2005, and RFC -4122 specify four algorithms for generating UUIDs, identified by the -version numbers 1, 3, 4, and 5. (There is no version 2 algorithm.) -Each of these algorithms could be suitable for a different set of -applications. - -uuid_generate_v1() -~~~~~~~~~~~~~~~~~~ - -This function generates a version 1 UUID. This involves the MAC -address of the computer and a time stamp. Note that UUIDs of this -kind reveal the identity of the computer that created the identifier -and the time at which it did so, which might make it unsuitable for -certain security-sensitive applications. - -uuid_generate_v1mc() -~~~~~~~~~~~~~~~~~~~~ - -This function generates a version 1 UUID but uses a random multicast -MAC address instead of the real MAC address of the computer. - -uuid_generate_v3(namespace uuid, name text) -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -This function generates a version 3 UUID in the given namespace using -the specified input name. The namespace should be one of the special -constants produced by the uuid_ns_*() functions shown below. (It -could be any UUID in theory.) The name is an identifier in the -selected namespace. For example: - - uuid_generate_v3(uuid_ns_url(), 'http://www.postgresql.org') - -The name parameter will be MD5-hashed, so the cleartext cannot be -derived from the generated UUID. - -The generation of UUIDs by this method has no random or -environment-dependent element and is therefore reproducible. - -uuid_generate_v4() -~~~~~~~~~~~~~~~~~~ - -This function generates a version 4 UUID, which is derived entirely -from random numbers. - -uuid_generate_v5(namespace uuid, name text) -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -This function generates a version 5 UUID, which works like a version 3 -UUID except that SHA-1 is used as a hashing method. Version 5 should -be preferred over version 3 because SHA-1 is thought to be more secure -than MD5. - - -UUID Constants --------------- - - uuid_nil() - -A "nil" UUID constant, which does not occur as a real UUID. - - uuid_ns_dns() - -Constant designating the DNS namespace for UUIDs. - - uuid_ns_url() - -Constant designating the URL namespace for UUIDs. - - uuid_ns_oid() - -Constant designating the ISO object identifier (OID) namespace for -UUIDs. (This pertains to ASN.1 OIDs, unrelated to the OIDs used in -PostgreSQL.) - - uuid_ns_x500() - -Constant designating the X.500 distinguished name (DN) namespace for -UUIDs. |