| MEM(4) | Device Drivers Manual (acorn32) | MEM(4) | 
mem, kmem —
/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. Only offsets within the bounds of
  /dev/mem are allowed.
Kernel virtual memory is accessed through the interface
    /dev/kmem in the same manner as
    /dev/mem. Only kernel virtual addresses that are
    currently mapped to memory are allowed.
On Acorn RiscPC, A7000(+) and RC7500 systems the I/O memory space
    (podule space and SuperIO) begins at physical address 0x03000000 and runs to
    0x033fffff. On the RiscPC, EASI space runs from 0x08000000 to 0x0fffffff.
    The per-process data size for the current process is
    UPAGES long, and starts at VM_MAXUSER_ADDRESS.
mem, kmem files appeared in
  Version 6 AT&T UNIX.
| July 28, 1995 | NetBSD 10.1 |