Proc/Ioports; Proc/Kcore; Proc/Kmsg - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

The first column displays the memory registers used by each of the different types of memory. The
second column lists the kind of memory located within those registers and displays which memory
registers are used by the kernel within the system RAM or, if the network interface card has multiple
Ethernet ports, the memory registers assigned for each port.

3.2.13. /proc/ioports

The output of /proc/ioports provides a list of currently registered port regions used for input or
output communication with a device. This file can be quite long. The following is a partial listing:
0000-001f : dma1
0020-003f : pic1
0040-005f : timer
0060-006f : keyboard
0070-007f : rtc
0080-008f : dma page reg
00a0-00bf : pic2
00c0-00df : dma2
00f0-00ff : fpu
0170-0177 : ide1
01f0-01f7 : ide0
02f8-02ff : serial(auto)
0376-0376 : ide1
03c0-03df : vga+
03f6-03f6 : ide0
03f8-03ff : serial(auto)
0cf8-0cff : PCI conf1
d000-dfff : PCI Bus #01
e000-e00f : VIA Technologies, Inc. Bus Master IDE
e000-e007 : ide0
e008-e00f : ide1
e800-e87f : Digital Equipment Corporation DECchip 21140 [FasterNet]
e800-e87f : tulip
The first column gives the I/O port address range reserved for the device listed in the second column.

3.2.14. /proc/kcore

This file represents the physical memory of the system and is stored in the core file format. Unlike
most /proc/ files, kcore displays a size. This value is given in bytes and is equal to the size of the
physical memory (RAM) used plus 4 KB.
The contents of this file are designed to be examined by a debugger, such as gdb, and is not human
readable.
Caution
Do not view the /proc/kcore virtual file. The contents of the file scramble text output on
the terminal. If this file is accidentally viewed, press Ctrl+C to stop the process and then
type reset to bring back the command line prompt.

3.2.15. /proc/kmsg

This file is used to hold messages generated by the kernel. These messages are then picked up by
other programs, such as /sbin/klogd or /bin/dmesg.
/proc/ioports
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