xref: /csrg-svn/share/man/man4/man4.tahoe/mem.4 (revision 30149)
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@(#)mem.4 6.1 (Berkeley) 11/24/86

MEM 4 ""
C 7
NAME
mem, kmem - main memory
DESCRIPTION
.lg Mem is a special file that is an image of the main memory of the computer. It may be used, for example, to examine (and even to patch) the system.

Byte addresses in mem are interpreted as physical memory addresses. References to non-existent locations cause errors to be returned.

Examining and patching device registers is likely to lead to unexpected results when read-only or write-only bits are present.

The file kmem is the same as mem except that kernel virtual memory rather than physical memory is accessed.

On TAHOE, the I/O page begins at physical address 0xfff00000 of kmem and per-process data for the current process begins at virtual 0xbffff000.

FILES
/dev/mem, /dev/kmem
BUGS
Memory files are accessed one byte at a time, an inappropiate method for some device registers.