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<?php ini_set('session.hash_function','sha512'); session_start(); $orig = session_id(); session_regenerate_id(); $new = session_id(); var_dump($orig,$new); session_commit(); ini_set('session.hash_function','sha1'); session_start(); $orig = session_id(); session_regenerate_id(); $new = session_id(); var_dump($orig,$new);

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