NAME    [Toc]    [Back]

     mem, kmem - memory files

DESCRIPTION    [Toc]    [Back]

     The file /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.

SPARC64    [Toc]    [Back]

     On the sparc64, physical memory may be discontiguous; kernel
virtual memory
 begins at 0x001000000.

     Writeability  of  these  devices is controlled by the system
securelevel(7).

FILES    [Toc]    [Back]

     /dev/mem
     /dev/kmem

SEE ALSO    [Toc]    [Back]

     securelevel(7)

HISTORY    [Toc]    [Back]

     The /dev/mem and /dev/kmem files appeared in Version 6  AT&T
UNIX.

OpenBSD      3.6                          October     5,     2001