Date: Mon, 27 Jul 92 11:40:15 EDT
From: DJ Delorie <dj AT ctron DOT com>
To: alvin AT eyepoint DOT on DOT ca
Cc: hideki AT isl DOT rdc DOT toshiba DOT co DOT jp, djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: cross compilation for DJ1.0x

>On the other issue the text should start at 0x1020 and not 0x20. This is because
>the first page of memory(4K,0x1000) is left unallocated forcing any referances
>to it to  cause a page fault, so that null pointer referances will cause
>a trapable error. 

To make this statement official and clear it up a bit: All file
references are read at 4k boundaries - always whole sectors.  Paging
always happens on page boundaries.  Thus, the first 4096 characters of
the actual file are loaded into the *second* 4096 bytes of program
space.  Thus, the byte at 0x20 in the file is loaded at 0x1020 in
virtual space.

DJ
dj AT ctron DOT com
Life is a banana.