Date: Sun, 28 May 2000 13:23:32 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: djgpp AT delorie DOT com
Subject: Re: MASM coff images
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On Sun, 28 May 2000, Steamer wrote:

> >PUBLIC _setText
> >_setText PROC C
> >  mov ah, 0
> >  mov al, 3
> >  int 10
> >  ret
> >_setText ENDP
> 
> You can't call real-mode BIOS interrupts directly from 32-bit protected
> mode and expect it work.

Actually, you can.  The interrupt gets reflected to real mode, and if the 
function is register-based (i.e., does not involve any buffers), like in 
this case, it will work.

It *is* true that calling interrupts via DPMI is the recommended way,
though.

> >gcc vgatest.c vga.obj -Wall -g -o vgatest.exe
> 
> Probably you need to rename vga.obj to vga.o, as I'm not sure that
> gcc recognises .obj as an object file extension.

I don't think this matters: any file with an unknown extension is
handled as if it were an object file.

I think running objdump with different switches on vga.obj will reveal 
what does the compiler and the linker think about that file.