Linux and UNIX Man Pages

Test Your Knowledge in Computers #977
Difficulty: Medium
A Linux Kernel Code of Conflict was introduced on 8 March 2012.
True or False?
Linux & Unix Commands - Search Man Pages

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 non-existent 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:mem /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:mem /dev/kmem Port is similar to mem, but the IO 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) Linux 1992-11-21 MEM(4)

Featured Tech Videos