Newsgroups: comp.os.minix Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!bronze!abadia@copper.ucs.indiana.edu From: antonio badia Subject: a Macminix question for experts Message-ID: <1991Jun25.172141.18466@bronze.ucs.indiana.edu> Sender: Organization: Indiana University Date: Tue, 25 Jun 91 12:21:27 -0500 Lines: 21 Hi there. Could anybody out there explain to me what the contents of shadow.c in kernel (in the Mac version of Minix) are about? The beginning of the file says: "this file performs shadowing, a solution for the fork() problem on machines that have no relocation hardware." My questions are: - I assume that relocation is the stuff that Tanenbaum mentions in his book, page 197. But, what exactly is the fork() problem? - it seems that this file (and consequently, the problem) does not exist in PCs. How come? I thought that PCs do not have this hardware, either. - what is the shadowing solution? -I added a few fields at the end of the proc declaration (proc.h) and when I launched the new Macboot I received a panic message from the shadows.c file ("only shadow(s)") while loading!. What is the relation between the shadowing stuff and the proc table (kernel part)? I'd appreciate any information, since my Assistant Instructor says he doesn't know what's going on and I have an assignment to do anyway. Thanks, Antonio abadia@copper.ucs.indiana.edu P.S. Joe Pickert, are you still alive out there?