php man page for session_write_close

SESSION_WRITE_CLOSE(3)							 1						    SESSION_WRITE_CLOSE(3)

session_write_close - Write session data and end session

SYNOPSIS
       void session_write_close (void  )

DESCRIPTION
	End the current session and store session data.

	Session data is usually stored after your script terminated without the need to call session_write_close(3), but as session data is locked
       to prevent concurrent writes only one script may operate on a session at any time. When using framesets together  with  sessions  you  will
       experience  the	frames loading one by one due to this locking. You can reduce the time needed to load all the frames by ending the session
       as soon as all changes to session variables are done.

RETURN VALUES
	No value is returned.

SEE ALSO
	The session_register_shutdown(3).

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