Uniqid returning similar value every time
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I'm generating a 5 letter uniqid in PHP this way:

    $id = substr(uniqid(),0,5);

And every single time I call it, I get the value `5004b`. Why is that happening?

If I remove the `substr`, the `5004b` part stays constant while the remaining changes. Isn't this severely reducing the entropy of the GUID being generated?