/dev/mem
is an interface to the physical memory of the
computer.
Byte offsets in this file are interpreted as physical memory addresses.
Reading and writing this file is equivalent to reading and writing
memory itself.
An error will be returned if an attempt is made to reference
an offset outside of
/dev/mem
.
Kernel virtual memory is accessed via the file
/dev/kmem
in the same manner as
/dev/mem
.
Only kernel virtual addresses that are currently mapped to memory are allowed.
On the Sun2, kernel virtual memory begins at
/dev/mem
/dev/kmem
AT&T UNIX
.