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mem(4) [v7 man page]

MEM(4)							     Kernel Interfaces Manual							    MEM(4)

NAME
mem, kmem - core memory DESCRIPTION
Mem is a special file that is an image of the core memory of the computer. It may be used, for example, to examine, and even to patch the system. Kmem is the same as mem except that kernel virtual memory rather than physical memory is accessed. Byte addresses are interpreted as memory addresses. References to non-existent locations return errors. Examining and patching device registers is likely to lead to unexpected results when read-only or write-only bits are present. On PDP11's, the I/O page begins at location 0160000 of kmem and per-process data for the current process begins at 0140000. FILES
/dev/mem, /dev/kmem BUGS
On PDP11's, memory files are accessed one byte at a time, an inapproriate method for some device registers. MEM(4)

Check Out this Related Man Page

MEM(4)							     Linux Programmer's Manual							    MEM(4)

NAME
mem, kmem, port - system memory, kernel memory and system ports DESCRIPTION
mem is a character device file that is an image of the main memory of the computer. It may be used, for example, to examine (and even patch) the system. Byte addresses in mem are interpreted as physical memory addresses. References to nonexistent locations cause errors to be returned. Examining and patching is likely to lead to unexpected results when read-only or write-only bits are present. It is typically created by: mknod -m 660 /dev/mem c 1 1 chown root:kmem /dev/mem The file kmem is the same as mem, except that the kernel virtual memory rather than physical memory is accessed. It is typically created by: mknod -m 640 /dev/kmem c 1 2 chown root:kmem /dev/kmem port is similar to mem, but the I/O ports are accessed. It is typically created by: mknod -m 660 /dev/port c 1 4 chown root:mem /dev/port FILES
/dev/mem /dev/kmem /dev/port SEE ALSO
chown(1), mknod(1), ioperm(2) COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 1992-11-21 MEM(4)
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