1*61581Sbostic.\" Copyright (c) 1991, 1993 2*61581Sbostic.\" The Regents of the University of California. All rights reserved. 347676Scael.\" 448960Scael.\" %sccs.include.redist.roff% 547676Scael.\" 6*61581Sbostic.\" @(#)mem.4 8.1 (Berkeley) 06/05/93 748225Sbostic.\" 848960Scael.Dd 948960Scael.Dt MEM 4 i386 1048960Scael.Os 1148960Scael.Sh NAME 1248960Scael.Nm mem , 1348960Scael.Nm kmem 1448960Scael.Nd memory files 1548960Scael.Sh DESCRIPTION 1648960ScaelThe special file 1748960Scael.Nm /dev/mem 1848960Scaelis an interface to the physical memory of the computer. 1948960ScaelByte offsets in this file are interpreted as physical memory addresses. 2048960ScaelReading and writing this file is equivalent to reading and writing 2148960Scaelmemory itself. 2248960ScaelOnly offsets within the bounds of 2348960Scael.Nm /dev/mem 2448960Scaelare allowed. 2548960Scael.Pp 2648960ScaelKernel virtual memory is accessed through the interface 2748960Scael.Nm /dev/kmem 2848960Scaelin the same manner as 2948960Scael.Nm /dev/mem . 3048960ScaelOnly kernel virtual addresses that are currently mapped to memory are allowed. 3148960Scael.Pp 3248960ScaelOn 3348960Scael.Tn ISA 3448960Scaelthe 3548960Scael.Tn I/O 3648960Scaelmemory space begins at physical address 0x000a0000 3747676Scaeland runs to 0x00100000. 3848960ScaelThe 3948960Scaelper-process data 4048960Scaelsize 4148960Scaelfor the current process 4248960Scaelis 4348960Scael.Dv UPAGES 4448960Scaellong, and ends at virtual 4547676Scaeladdress 0xfe000000. 4648960Scael.Sh FILES 4748960Scael.Bl -tag -width Pa -compact 4848960Scael.It Pa /dev/mem 4948960Scael.It Pa /dev/kmem 5048960Scael.El 5148960Scael.Sh HISTORY 5248960ScaelThe 5348960Scael.Nm mem , 5448960Scael.Nm kmem 5548960Scaelfiles appeared in 5648960Scael.At v6 . 57