| MEM(4) | Device Drivers Manual (x86) | MEM(4) |
mem, kmem —
memory files
The special 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. 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 ISA the I/O memory space begins at physical address 0x000a0000 and runs to 0x00100000.
The mem, kmem
files appeared in Version 6 AT&T
UNIX.
| March 27, 2026 | NetBSD 11.99 |