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+--- Thread: Unique ID for user directory ? (/showthread.php?tid=36541)
Unique ID for user directory ? - El Forum - 12-05-2010
[eluser]mci[/eluser]
Hi
I need a unique ID for user directories. Will
Code:
md5(uniqid());Unique ID for user directory ? - El Forum - 12-05-2010
[eluser]WanWizard[/eluser]
Try to avoid uniqueid(), it's not very portable. It also generates id's which are hex values of the current time, not necessarily that unique.
Instead, I would go for UUID's. There's a PECL extension for it, and there are also native PHP versions floating around.
Unique ID for user directory ? - El Forum - 12-05-2010
[eluser]mci[/eluser]
Thank you. Do you have a recommendation which extension or class I should use?
Unique ID for user directory ? - El Forum - 12-05-2010
[eluser]WanWizard[/eluser]
PECL is handy, but requires control over the PHP installation (which you might not have in all cases) so you can install it.
Alternatively, you can use this PHP function:
Code:
function gen_uuid() {
return sprintf( 'xx-x-x-x-xxx',
// 32 bits for "time_low"
mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ),
// 16 bits for "time_mid"
mt_rand( 0, 0xffff ),
// 16 bits for "time_hi_and_version",
// four most significant bits holds version number 4
mt_rand( 0, 0x0fff ) | 0x4000,
// 16 bits, 8 bits for "clk_seq_hi_res",
// 8 bits for "clk_seq_low",
// two most significant bits holds zero and one for variant DCE1.1
mt_rand( 0, 0x3fff ) | 0x8000,
// 48 bits for "node"
mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff )
);
}