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hd(4) [suse man page]

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

hd - MFM/IDE hard disk devices DESCRIPTION
The hd* devices are block devices to access MFM/IDE hard disk drives in raw mode. The master drive on the primary IDE controller (major device number 3) is hda; the slave drive is hdb. The master drive of the second controller (major device number 22) is hdc and the slave hdd. General IDE block device names have the form hdX, or hdXP, where X is a letter denoting the physical drive, and P is a number denoting the partition on that physical drive. The first form, hdX, is used to address the whole drive. Partition numbers are assigned in the order the partitions are discovered, and only nonempty, nonextended partitions get a number. However, partition numbers 1-4 are given to the four partitions described in the MBR (the "primary" partitions), regardless of whether they are unused or extended. Thus, the first logi- cal partition will be hdX5. Both DOS-type partitioning and BSD-disklabel partitioning are supported. You can have at most 63 partitions on an IDE disk. For example, /dev/hda refers to all of the first IDE drive in the system; and /dev/hdb3 refers to the third DOS "primary" partition on the second one. They are typically created by: mknod -m 660 /dev/hda b 3 0 mknod -m 660 /dev/hda1 b 3 1 mknod -m 660 /dev/hda2 b 3 2 ... mknod -m 660 /dev/hda8 b 3 8 mknod -m 660 /dev/hdb b 3 64 mknod -m 660 /dev/hdb1 b 3 65 mknod -m 660 /dev/hdb2 b 3 66 ... mknod -m 660 /dev/hdb8 b 3 72 chown root:disk /dev/hd* FILES
/dev/hd* SEE ALSO
chown(1), mknod(1), sd(4), mount(8) COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at Linux 1992-12-17 HD(4)

Check Out this Related Man Page

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

mem, kmem, port - system memory, kernel memory and system ports DESCRIPTION
/dev/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 /dev/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. Since Linux 2.6.26, and depending on the architecture, the CONFIG_STRICT_DEVMEM kernel configuration option limits the areas which can be accessed through this file. For example: on x86, RAM access is not allowed but accessing memory-mapped PCI regions is. It is typically created by: mknod -m 660 /dev/mem c 1 1 chown root:kmem /dev/mem The file /dev/kmem is the same as /dev/mem, except that the kernel virtual memory rather than physical memory is accessed. Since Linux 2.6.26, this file is available only if the CONFIG_DEVKMEM kernel configuration option is enabled. It is typically created by: mknod -m 640 /dev/kmem c 1 2 chown root:kmem /dev/kmem /dev/port is similar to /dev/mem, but the I/O ports are accessed. It is typically created by: mknod -m 660 /dev/port c 1 4 chown root:kmem /dev/port FILES
/dev/mem /dev/kmem /dev/port SEE ALSO
chown(1), mknod(1), ioperm(2) COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at Linux 2015-01-02 MEM(4)

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