Message-Id: Comments: Authenticated sender is From: "Salvador Eduardo Tropea (SET)" Organization: INTI To: sandmann AT clio DOT rice DOT edu (Charles Sandmann), eliz AT is DOT elta DOT co DOT il Date: Wed, 22 Jul 1998 17:00:57 +0000 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Subject: Re: Ispell and pipes CC: djgpp-workers AT delorie DOT com In-reply-to: <9807221938.AA12935@clio.rice.edu> References: from "Eli Zaretskii" at Jul 22, 98 05:40:17 pm Precedence: bulk Charles wrote: > > > > If you think about using the usual DJGPP RMCBs, then I think they > > > > *must* be locked, or CWSDPMI will abort your program. Charles, am I > > > > right here? > > > > > > Sorry, I fail to catch the idea, what do you think we must lock and > > > why? > > > > Charles once told me that CWSDPMI imposes a limitation on RMCBs, for > > safety reasons, and the upshot is that you must lock every code and data > > that is called by an RMCB. But I'm not sure I got it right, so I will > > wait for Charles to give the definitive answer. > > If a RMCB comes into CWSDPMI ... you are never sure what state DOS is in. > A mouse call back may have interrupted DOS - and if you need to page fault > you would re-enter DOS, which can destroy your hard disk. > > So, if you used the RMCB you would have to lock the buffers that you take > bytes out of and the code, but this would be fairly small and localized. But we want to make it: DJGPP program B calls a real mode function, the real mode funtion is a RMCB that was created by djgpp program A so the execution jumps to program A. As program B is in protected mode and in normal execution (not inside an ISR) we are shure that DOS isn't busy. That's our case. Now Eli question is if we need to lock the code just because CWSDPMI will check it even when DOS isn't busy. > BTW - with my travel schedule it may sometimes take up to a week before I > can reply to these things... Ok. Greetings, SET ------------------------------------ 0 -------------------------------- Visit my home page: http://set-soft.home.ml.org/ or http://www.geocities.com/SiliconValley/Vista/6552/ Salvador Eduardo Tropea (SET). (Electronics Engineer) Alternative e-mail: set-soft AT usa DOT net set AT computer DOT org ICQ: 2951574 Address: Curapaligue 2124, Caseros, 3 de Febrero Buenos Aires, (1678), ARGENTINA TE: +(541) 759 0013