Date: Thu, 4 Feb 1999 13:25:47 +0200 (IST) From: Eli Zaretskii X-Sender: eliz AT is To: silkwodj AT my-dejanews DOT com cc: djgpp AT delorie DOT com Subject: Re: executible formats In-Reply-To: <799uob$ku3$1@nnrp1.dejanews.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: djgpp AT delorie DOT com On Wed, 3 Feb 1999 silkwodj AT my-dejanews DOT com wrote: > P.S. I tried to reproduce a DPMI call (segment_to_selector) by preparing my > own NASM function, based on the wrapper source. Worked fine in DJGPP. Took > the same module with the int 33h call and assembled to WIN32 (OBJ) and linked > with MSVC(either 4.2 or 5.0, I forget) compiled fine, but execution locked up > the machine with a black screen (really scarry). Am I bumping into something > new? AFAIK, this is just one of those free gifts you get from Microsoft: Win32 programs cannot issue software interrupts, including Int 31h (I'm guessing you meant 31h and not 33h, which is a mouse interrupt), because the software interrupt handler is in the VMM which assumes the caller is 16-bit code, and thus only saves the 16-bit registers on the stack.