- ...devices.
- See mknod(1,2) for an explanation of
how to make these files.
- ...numbers.
- This is not strictly true, but is close enough. If
you understand where it is not true, you don't need to read this
section, and if you don't but want to learn, read the code for the tty
devices, which uses up 2 major numbers, and may use a third and
possibly fourth by the time you read this.
- .../dev/mouse.
- Even though XFree86 is now able to read PS/2
style ``droppings'', the concepts in this example still stand. If
you have a better example, I'd be glad to see it.
- ...register_chrdev().
- See section

- ...details.
- Although SCSI disks and CDROMs are block devices,
SCSI tapes, like other tapes, are generally used as character
devices.
- ...disk.
- A used 20 MB MFM
hard disk and controller should cost less than US$100.
- ...helpful.
- The October 17, 1991, draft
of the SCSI-2 standard document is available via anonymous ftp from
sunsite.unc.edu
in /pub/Linux/development/scsi-2.tar.Z
, and
is available for purchase from Global Engineering Documents (2805 McGaw,
Irvine, CA 92714), (800)-854-7179 or (714)-261-1455. Please refer to
document X3.131-199X. In early 1993, the manual cost US$60--70.
- ...interrupt-driven,
- Some of the early drivers were not
interrupt driven and, consequently, had very poor performance.
- ...interleave,
- ``1:1 interleave'' means that all of the sectors in a
single track appear consecutively on the disk surface.
- ...sectors.
- This may be an
over-simplification. On older devices, the actual command processing can
be significant. Further, there is a great deal of layered overhead in
the kernel: the high-level SCSI code, the buffering code, and the
file-system code all contribute to poor SCSI performance.
- ...bus
- The
so-called ``Industry Standard Architecture'' bus was introduced with the
IBM PC/XT and IBM PC/AT computers.
- ...bus
- The
``Extended Industry Standard Architecture'' bus is a non-proprietary
32-bit bus for 386 and i486 machines.
- ...bus
- The
``Micro-Channel Architecture'' bus is IBM's proprietary 32 bit bus for
386 and i486 machines.
- ...code
- 0.99.7 kernel source code,
linux/kernel/irq.c
- ...declaration
- 0.99.5 kernel source code,
linux/kernel/irq.c
- ...definition
- 0.99.5 kernel source code,
linux/include/linux/signal.h
- ...#figcommand#1367>.
- 0.99.5 kernel,
linux/kernel/blk_drv/scsi/aha1542.c, written by Tommy Thorn.
- ...MS-DOS
- MS-DOS is a registered trademark of
Microsoft Corporation.
- ...structure,
- 0.99.7 kernel,
linux/kernel/blk_drv/scsi/scsi.h
- ...are,
- Usually a file called a namelist file, often
/etc/psdatabase.
- ...steps:
- Unless you are making a
subdirectory of the replicating, dynamically allocated process
directory, you would have to create a new filesystem type, similar to
the proc filesystem in design. Subdirectories of the process
directories are supported by the mechanism which dynamically creates
the process directories. I suggest going through this explanation of
how to add a non-dynamically-allocated directory, understand it, and
then read the code for the process subdirectories, if you wish to add
subdirectories to the process subdirectories.
- ...model:
- This file is available as file proc/foo.c in the
The Linux Kernel Hackers' Guide
source mentioned on the copyright page.
- ...addresses
- In the
80386, linear address run from 0GB to 4GB. A linear address points to
a particular memory location within this space. A linear address is
not a physical address --- it is a virtual address.
- ...addresses
- A logical address consists of a selector and an
offset. The selector points to a segment and the offset tells how far
into that segment the address is located.
- ...task
- Sometimes called the swapper
task, even though it has nothing to do with swapping in the \
implementation, for historical reasons
Ross Biro
Mon May 22 11:57:09 PDT 1995