🚀 go-pugleaf

Frank E. Prince (fprince@cwis.unomaha.edu) wrote:
: Could anyone tell me the difference between .com and .exe files. The
: most I've come up with is that a com file is an "executable memory image"
: but that definition was somewhat out of context, and I don't really
: understand it. I've done some assembly language programming with MASM so
: I do understand instruction sets, stacks, registers etc. Any information
: regarding this is much appreciated.

	Quit simple.  EXE file upon loading have far pointer
references within them altered at program start up since the i86 code
cannot have RELATIVE far calls and jumps.  SO in order to specify the
proper address a table of pointer is loaded.  Each point contains the
address of a "relocatable" item.  IE the far calls and pointers.  

	A com file is much faster in loading because it uses the Tiny
memory model and therefore there is no need for the screwy relcoation
method EXE's have to use (if they want to address > 64k segments)

Cyberman
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