add a couple of examples, and generally elaborate more on the subject

1 files changed, 23 insertions, 2 deletions

diff --git a/sys/arch/i386/stand/boot/boot.8 b/sys/arch/i386/stand/boot/boot.8
index 6070fcdd338..c4b5cb4982f 100644
--- a/sys/arch/i386/stand/boot/boot.8
+++ b/sys/arch/i386/stand/boot/boot.8
@@ -1,6 +1,6 @@
-.\"	$OpenBSD: boot.8,v 1.18 2000/07/12 20:19:23 deraadt Exp $
+.\"	$OpenBSD: boot.8,v 1.19 2000/08/07 20:30:34 mickey Exp $
 .\"
-.\" Copyright (c) 1997-1999 Michael Shalayeff
+.\" Copyright (c) 1997-2000 Michael Shalayeff
 .\" All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
@@ -159,6 +159,27 @@ Meaning to add(+) or exempt(-) the specified by the
 amount of memory at the location specified by the
 .Ar <address>
 argument.
+Both size and base address could be specified as octal,
+decimal, or hexadecimal numbers, as accepted by the
+.Xr stroul 3
+routine.
+Memory segments are not required to be adjucent to each other,
+the only requirement is that there is real physical memory under
+the range added.
+For example:
+.Bd -unfilled -offset indent
+machine mem +0x2000000@0x1000000
+.Ed
+.Pp
+would add 32M of memory right after first 16M.
+The other usefull command would be to winthdraw some range
+of memory form OS usage (as might be wrongfully reported as
+usefull by BIOS):
+.Bd -unfilled -offset indent
+machine mem -0x100000@0xf00000
+.Ed
+.Pp
+which effectively excludes 15-16M range from the map of usefull memory.
 .It Nm regs
 Prints contents of processor registers if compiled with
 .Em DEBUG .