Invisible wrote:
> Connect two outputs together,

I don't think two outputs would have a gate between them like that. However, 
at this point I'm really over my head. I've never *actually* written 
microcode for a real computer myself. :-)

> OK. So what's all this stuff about "the OS loads programs by memory 
> mapping them"? (Hopefully this will explain why programs show up as 
> generating a non-zero number of "page faults", even though no swapping 
> is actually happening...)

It's exactly the same thing. If you have a chunk of executable that's 
supposed to be in addresses 0x1000 to 0x3000, and that's at offset zero in 
the file, you memmap the file into the page tables. Basically, you use the 
executable file itself as the swap file for that region of memory.

That's why in UNIX you can delete a running executable file, but you can't 
write to it. Because you're actually running code right out of the file, and 
not a copy of the file.

-- 
Darren New, San Diego CA, USA (PST)
  "How did he die?"   "He got shot in the hand."
     "That was fatal?"
          "He was holding a live grenade at the time."

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