edmoy@ucbopal.CC.Berkeley.ARPA (06/05/85)
From poking around with MacsBug, I discovered that the file ref number is the offset within the File-Control-Block Buffer to the file's control block. This buffer is pointed to by fcbSPtr (0x34e). Normally, the System file has a ref number of 2, which skips over the length word at the beginning of the buffer (see Inside Macintosh, File Manager, pg 61). Within the file control block is fcbVPtr (offset 20), a pointer to the volume control block for the file. And within the volume control block is vcbVRefNum (pg 59), the volume reference number. Simple, right?!?!? Good luck! Edward Moy Academic Computing Services University of California Berkeley, CA 94720 edmoy@ucbopal.APRA ucbvax!ucbopal!edmoy