Description:
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Hello,

In short, while a session is in progress, or running, we are not able to remove sess_* files by using unlink(). Yet, when a session is not active, I can remove all the files freely. There is nothing about this in the documentation, and there seems to be this issue all over forums searched from google. I feel this is a bug, as PHP should deny removing files while a session is active.

The following produces this error "Warning: unlink(./tmp/sess_2b8185697c7b9d826773403c1477041f) [function.unlink]: Permission denied in X:\path\to\script.php on line 0"

<?php
  define("_PATH_TMP", "X:/dir/to/my/tmp");
  ini_set('session.save_path', _PATH_TMP);
  session_start(); 
  $_SESSION['sid']['obsolete'] = session_id();
  session_regenerate_id();
  $_SESSION['sid']['replaced'] = session_id();
  unlink('./tmp/' . $_SESSION['sid']['obsolete'])
  print_r($_SESSION);
?>

As well, the garbage collection doesnt seem to be working, all I see is my sessions keep piling up since I have my script regenerate an id, thus create a new file in my defined tmp directory. If session_set_cookie_params worked properally, I would beable to define both id's thus to say I could unlink the file with $_COOKIE['sid']['obsolete'].

As well, as I read apon session_regenerate_id() its suppose to remove the file apon complition... well, in short, its not!