debian man page for data::uuid::libuuid

Data::UUID::LibUUID(3pm)				User Contributed Perl Documentation				  Data::UUID::LibUUID(3pm)

NAME
       Data::UUID::LibUUID - uuid.h based UUID generation (versions 2 and 4 depending on platform)

SYNOPSIS
	   use Data::UUID::LibUUID;

	   my $uuid = new_uuid_string();

DESCRIPTION
       This module provides bindings for libuuid shipped with e2fsprogs or uuid-dev on debian, and also works with the system uuid.h on darwin.

EXPORTS
       new_uuid_string $version
       new_uuid_binary $version
	   Returns a new UUID in string (dash separated hex) or binary (16 octets) format.

	   $version can be either 2, or 4 and defaults to whatever the underlying implementation prefers.

	   Version 1 is timestamp/MAC based UUIDs, like Data::UUID provides. They reveal time and host information, so they may be considered a
	   security risk.

	   Version 2 is described here <http://www.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01>.  It is similar to version 1
	   but considered more secure.

	   Version 4 is based just on random data. This is not guaranteed to be high quality random data, but usually is supposed to be.

	   On MacOS X "getpid" is called before UUID generation, to ensure UUIDs are unique accross forks. Behavior on other platforms may vary.

       uuid_to_binary $str_or_bin
	   Converts a UUID from string or binary format to binary format.

	   Returns undef on a non UUID argument.

       uuid_to_string $str_or_bin
	   Converts a UUID from string or binary format to string format.

	   Returns undef on a non UUID argument.

       uuid_eq $str_or_bin, $str_or_bin
	   Checks if two UUIDs are equivalent. Returns true if they are, or false if they aren't.

	   Returns undef on non UUID arguments.

       uuid_compare $str_or_bin, $str_or_bin
	   Returns -1, 0 or 1 depending on the lexicographical order of the UUID. This works like the "cmp" builtin.

	   Returns undef on non UUID arguments.

       new_dce_uuid_string
       new_dce_uuid_binary
	   These two subroutines are a little hackish in that they take no arguments but also do not validate the arguments, so they can be abused
	   as methods:

	       package MyFoo;

	       use Data::UUID::LibUUID (
		   new_dce_uuid_string => { -as "generate_uuid" },
	       );

	       sub yadda {
		   my $self = shift;
		   my $id = $self->generate_uuid;
	       }

	   This allows the ID generation code to be subclassed, but still keeps the hassle down to a minimum. DCE is UUID version two
	   specification.

       ascending_ident
	   Creates a lexically ascending identifier containing a UUID, high resolution timestamp, and a counter.

	   This is not a UUID (it's longer), but if you can store variable length identifier (and exposing the system clock is not an issue) they
	   can be used to create an identifier that is both universally unique, and lexically increasing.

	   Note that while the identifiers are universally unique, there is no universal ordering (that would require synchronization), so
	   identifiers generated on different machines or even different process/thread could have IDs which interleave.

TODO
       o   Consider bundling libuuid for when no system "uuid.h" exists.

SEE ALSO
       Data::GUID, Data::UUID, UUID, <http://e2fsprogs.sourceforge.net/>

VERSION CONTROL
       This module is maintained using Darcs. You can get the latest version from <http://nothingmuch.woobling.org/code>, and use "darcs send" to
       commit changes.

AUTHOR
       Yuval Kogman <nothingmuch@woobling.org>

COPYRIGHT
	   Copyright (c) 2008 Yuval Kogman. All rights reserved
	   This program is free software; you can redistribute
	   it and/or modify it under the same terms as Perl itself.

perl v5.14.2							    2010-07-05						  Data::UUID::LibUUID(3pm)