ira@slovax.UUCP (02/16/87)
(I just received my copy of the Minix book and have only started reading it, so if the answer may be found there, I appologize up front.) The Set User ID bit in the directory is protected by United States patent number 4,135,240. Minix appears to have the same capability. Did Tanenbaum or Prentice-Hall license the patent from AT&T? If not, under what conditions can the Set User ID bit concept be employed without an AT&T license? While on the subject, does anyone know if the Set Group ID bit (which is not explicitly mentioned in the patent) is also covered by said patent?