Red Hat ENTERPRISE LINUX 3 Reference Manual page 67

proc
Chapter 5. The
Block devices:
1 ramdisk
2 fd
3 ide0
9 md
22 ide1
The output from
/proc/devices
into two major sections:
Character devices are similar to block devices, except for two basic differences:
1. Block devices have a buffer available, allowing them to order requests before addressing them.
This is important for devices designed to store information — such as hard drives — because
the ability to order the information before writing it to the device allows it to be placed in a more
efficient order. Character devices do not require buffering.
2. Block devices can send and receive information in blocks of a size configured per device. Char-
acter devices send data with no preconfigured size.
For more information about devices refer to the following installed documentation:
/usr/src/linux-2.4/Documentation/devices.txt
5.2.5.
/proc/dma
This file contains a list of the registered ISA direct memory access (DMA) channels in use. A sample
files looks like the following:
/proc/dma
4: cascade
5.2.6.
/proc/execdomains
This file lists the execution domains currently supported by the Linux kernel, along with the range of
personalities they support.
0-0 Linux
Think of execution domains as the "personality" for an operating system. Because other binary for-
mats, such as Solaris, UnixWare, and FreeBSD, can be used with Linux, programmers can change
the way the operating system treats system calls from these binaries by changing the personality of
the task. Except for the
dynamically loadable modules.
5.2.7.
/proc/fb
This file contains a list of frame buffer devices, with the frame buffer device number and the driver
that controls it. Typical output of
similar to the following:
0 VESA VGA
File System
includes the major number and name of the device, and is broken
Character devices
[kernel]
execution domain, different personalities can be implemented as
PER_LINUX
/proc/fb
and
Block devices
for systems which contain frame buffer devices looks
.
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