unique id for visitor

[Anon]

Does anybody know how i can give a visitor of my website a unique id?

Thanx

[Anon]

Hi
My guess would be make a string of numbers, which can be type casted later, from the date, time and a couple of random numbers(just in case). Woudl be something like this.

$unique_id = date("mdYHis").mk_rand(10,99);

We use this for generating purchase orders, order id's and works really fine for us.

[Anon]

See the manual page for uniqid().

[Anon]

I like adding the PID to the mix. And don't be put off by what it says in the manual about getmypid:

  Note that when running as a server module,
  separate invocations of the script are not guaranteed
  to have distinct pids

True enough, but concurrent invocations of the same script (or any
other script calling uniqueid) are going to have unique pid's and
by the time any single script finishes, the microtime on which uniqueid
is based will be providing a different value.