Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!ucsd!ucbvax!agate!ragu!lippin From: lippin@ragu.berkeley.edu (The Apathist) Newsgroups: comp.sys.mac.programmer Subject: Re: Drawing in the menu bar (AGAIN) Message-ID: <1990Aug14.031613.18374@agate.berkeley.edu> Date: 14 Aug 90 03:16:13 GMT References: <9536@goofy.Apple.COM> <2900@isc-br.ISC-BR.COM> <1816@mountn.dec.com> <2902@isc-br.ISC-BR.COM> Sender: usenet@agate.berkeley.edu (USENET Administrator;;;;ZU44) Reply-To: lippin@math.berkeley.edu Organization: Authorized Service, Incorporated Lines: 26 In article <1816@mountn.dec.com> minow@bolt.enet.dec.com (Martin Minow) writes: >EraseRect (to take one example) is explicitly marked as "may move >memory."... Recently jimc@isc-br.ISC-BR.COM (Jim Cathey) wrote: >Too bad. It used to be safe (See Appendix A of IM-III and IM-IV). Not by the IM-III I have here. It's a recent edition, but it claims not to have been changed. And I remember drawing at interrupt time being illegal even back when I was using the phone book edition. Also, the question of modifying regions hardly enters into the discussion -- the title of the list "Routines That May Move or Purge Memory" is a misnomer. It's really "Routines Which are Unsafe at Interrupt Time." You can't draw at interrupt time because QuickDraw isn't reentrant. It forgets, for example, whether the cursor is showing. Kind of confusing for normal use, but great for drawing pine forests in a high wind :-). --Tom Lippincott lippin@math.berkeley.edu "If it was so, then it would be, and if it were so, then it could be, but as it isn't, it ain't. That's Logic." --Tweedledee