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  1. Introduction
  2. Abbreviated Boot
  3. The Boot Process
  4. Startup and Run Levels
  5. Initialization Scripts
  6. Runlevel Scripts
  7. Login Process
  8. Bash Shell
  9. Filesystems
  10. LILO, Kernel and Root Filesystem
  11. The Kernel
  12. Passwords, Users, Groups, and Quotas
  13. The Environment
  14. The /etc/sysconfig directory
  15. The /proc filesystem
  16. Process Control
  17. Devices
  18. Daemons Services
  19. Inetd and Network Services
  20. Programs and Libraries
  21. Security and PAM
  22. The printer services
  23. Mouse support with gpm
  24. Mail
  25. News
  26. UUCP
  27. LDAP
  28. NFS and RPC
  29. Samba, NetBIOS, WINS, nmbd
  30. Identd (auth)
  31. Telnet and FTP
  32. Apache web server
  33. DNS and named
  34. How X Works
  35. X Scripts
  36. Support for Text
  37. Keymapping for Programs
  38. Keycode Table
  39. Example Keymap File
  40. Terminfo Commands
  41. VT100 ESC sequences
  42. Kernel Revisited
  43. Configuration Files
  44. Credits

LINUX Devices

The below table lists common Linux devices.

/dev/fd0Floppy disk
/dev/hda0IDE Hard drive 1, partition 0
/dev/hdb3IDE Hard drive 2, partition 3
/dev/sdaFirst SCSI hard drive
/dev/cdromCD ROM drive This device may be on the secondary controller as a master (/dev/hdc) or slave (/dev/hdd). In fact, your /dev/cdrom is probably actually a softlink to one of these two devices, if you have an IDE interface. If you use SCSI, you will probably use something like /dev/sda1 or 2, etc.
/dev/mouseMay be a pointer to /dev/psaux which is the ps2 device or /dev/cua which is a serial device or /dev/ttyS0

Some Disk Devices:

primary IDE master/dev/hda
primary IDE slave /dev/hdb
secondary IDE master/dev/hdc
secondary IDE slave/dev/hdd

Linux devices are merely files used to direct output and input through. They have to be supported by the kernel to work properly. How it exactly ties into the kernel and its modules, I am not yet sure. I do know that many devices are supported by modules such as "loop.o" for /dev/loop0..7. To add the module to the kernel, you must use the insmod command. See the section on "The Kernel", subsection "Kernel Module Support".

To make a device, type "mknod device device type major number minor number" For example, "mknod /tmp/psaux c 10 1" creates a character ps2 device with name "/dev/psaux" with major number 10, minor number 1. I believe there is a set numbering scheme for devices, but I'm not sure what it is. This could be how it ties into the kernel. The types of devices are:

  • c - character
  • u - unbuffered character
  • b - block
  • p - FIFO

The device driver major number really points to the device driver file in the /dev directory

General device numbering convention:

1char Memory devices
block RAM disk
2char Reserved for PTY's <>
block Floppy disks
3char Reserved for PTY's <>
block First MFM, RLL and IDE hard disk/CD-ROM interface
4char TTY devices
5char Alternate TTY devices
6char Parallel printer devices
7char Virtual console access devices
8block SCSI disk devices
9char SCSI tape devices
block Multiple disk devices
10char Non-serial mice, misc features
11block SCSI CD-ROM devices
12char QIC-02 tape
block MSCDEX CD-ROM callback support
13char PC speaker
block 8-bit MFM/RLL/IDE controller
14char Sound card
block BIOS hard drive callback support
15char Joystick
block Sony CDU-31A/CDU-33A CD-ROM
16char Reserved for scanners
block GoldStar CD-ROM
17char Chase serial card (Under development)
block Optics Storage CD-ROM (Under development)
18char Chase serial card - alternate devices
block Sanyo CD-ROM (Under development)
19char Cyclades serial card
block Double compressed disk
20char Cyclades serial card - alternate devices
block Hitachi CD-ROM (Under development)
21char Generic SCSI access
22char Digiboard serial card
block Second MFM, RLL and IDE hard disk/CD-ROM interface
23char Digiboard serial card - alternate devices
block Mitsumi proprietary CD-ROM
24char Stallion serial card
block Sony CDU-535 CD-ROM
25char Stallion serial card - alternate devices
block First Matsushita (Panasonic/SoundBlaster) CD-ROM
26block Second Matsushita (Panasonic/SoundBlaster) CD-ROM
27char QIC-117 tape
block Third Matsushita (Panasonic/SoundBlaster) CD-ROM
28char Stallion serial card - card programming
block Fourth Matsushita (Panasonic/SoundBlaster) CD-ROM
block ACSI disk (68k)
29char Universal frame buffer
block Aztech/Orchid/Okano/Wearnes CD-ROM
30char iBCS-2
block Philips LMS-205 CD-ROM
31char MPU-401 MIDI
block ROM/flash memory card
32block Philips LMS-206 CD-ROM
33block Modular RAM disk
224-254Local use