Asri-unix.391 net.unix-wizards utzoo!decvax!ucbvax!menlo70!sri-unix!dan@BBN-UNIX Thu Dec 31 21:57:56 1981 PDP-11 stack size From: Dan Franklin Seems like a workable way to get those last few bytes. But you don't need to change the u area to keep track of the "virtual" limit; the sbrk library routine (!) already does that privately. Merely changing estabur to be willing to map the whole address space is sufficient. To detect collisions between the stack and data, you could use the stack limit register, at least on the 11/45, 55, 60, and 70 (I don't know about the others). It provides 256-byte resolution, which is better than nothing. Its value would have to saved and restored across process switches. (This also assumes that the stack limit register works in user mode, which I have never had to verify.) ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.