Linux allocated devices (4.x+ version)¶
This list is the Linux Device List, the official registry of allocated
device numbers and /dev directory nodes for the Linux operating
system.
The LaTeX version of this document is no longer maintained, nor is the document that used to reside at lanana.org. This version in the mainline Linux kernel is the master document. Updates shall be sent as patches to the kernel maintainers (see the Submitting patches: the essential guide to getting your code into the kernel document). Specifically explore the sections titled “CHAR and MISC DRIVERS”, and “BLOCK LAYER” in the MAINTAINERS file to find the right maintainers to involve for character and block devices.
This document is included by reference into the Filesystem Hierarchy Standard (FHS). The FHS is available from https://www.pathname.com/fhs/.
Allocations marked (68k/Amiga) apply to Linux/68k on the Amiga platform only. Allocations marked (68k/Atari) apply to Linux/68k on the Atari platform only.
This document is in the public domain. The authors requests, however, that semantically altered versions are not distributed without permission of the authors, assuming the authors can be contacted without an unreasonable effort.
Attention
DEVICE DRIVERS AUTHORS PLEASE READ THIS
Linux now has extensive support for dynamic allocation of device numbering
and can use sysfs and udev (systemd) to handle the naming needs.
There are still some exceptions in the serial and boot device area. Before
asking for a device number make sure you actually need one.
To have a major number allocated, or a minor number in situations where that applies (e.g. busmice), please submit a patch and send to the authors as indicated above.
Keep the description of the device in the same format as this list. The reason for this is that it is the only way we have found to ensure we have all the requisite information to publish your device and avoid conflicts.
Finally, sometimes we have to play “namespace police.” Please don’t be
offended. We often get submissions for /dev names that would be bound
to cause conflicts down the road. We are trying to avoid getting in a
situation where we would have to suffer an incompatible forward
change. Therefore, please consult with us before you make your
device names and numbers in any way public, at least to the point
where it would be at all difficult to get them changed.
Your cooperation is appreciated.
0 Unnamed devices (e.g. non-device mounts)
0 = reserved as null device number
See block major 144, 145, 146 for expansion areas.
1 char Memory devices
1 = /dev/mem Physical memory access
2 = /dev/kmem OBSOLETE - replaced by /proc/kcore
3 = /dev/null Null device
4 = /dev/port I/O port access
5 = /dev/zero Null byte source
6 = /dev/core OBSOLETE - replaced by /proc/kcore
7 = /dev/full Returns ENOSPC on write
8 = /dev/random Nondeterministic random number gen.
9 = /dev/urandom Faster, less secure random number gen.
10 = /dev/aio Asynchronous I/O notification interface
11 = /dev/kmsg Writes to this come out as printk's, reads
export the buffered printk records.
12 = /dev/oldmem OBSOLETE - replaced by /proc/vmcore
1 block RAM disk
0 = /dev/ram0 First RAM disk
1 = /dev/ram1 Second RAM disk
...
250 = /dev/initrd Initial RAM disk
Older kernels had /dev/ramdisk (1, 1) here.
/dev/initrd refers to a RAM disk which was preloaded
by the boot loader; newer kernels use /dev/ram0 for
the initrd.
2 char Pseudo-TTY masters
0 = /dev/ptyp0 First PTY master
1 = /dev/ptyp1 Second PTY master
...
255 = /dev/ptyef 256th PTY master
Pseudo-tty's are named as follows:
* Masters are "pty", slaves are "tty";
* the fourth letter is one of pqrstuvwxyzabcde indicating
the 1st through 16th series of 16 pseudo-ttys each, and
* the fifth letter is one of 0123456789abcdef indicating
the position within the series.
These are the old-style (BSD) PTY devices; Unix98
devices are on major 128 and above and use the PTY
master multiplex (/dev/ptmx) to acquire a PTY on
demand.
2 block Floppy disks
0 = /dev/fd0 Controller 0, drive 0, autodetect
1 = /dev/fd1 Controller 0, drive 1, autodetect
2 = /dev/fd2 Controller 0, drive 2, autodetect
3 = /dev/fd3 Controller 0, drive 3, autodetect
128 = /dev/fd4 Controller 1, drive 0, autodetect
129 = /dev/fd5 Controller 1, drive 1, autodetect
130 = /dev/fd6 Controller 1, drive 2, autodetect
131 = /dev/fd7 Controller 1, drive 3, autodetect
To specify format, add to the autodetect device number:
0 = /dev/fd? Autodetect format
4 = /dev/fd?d360 5.25" 360K in a 360K drive(1)
20 = /dev/fd?h360 5.25" 360K in a 1200K drive(1)
48 = /dev/fd?h410 5.25" 410K in a 1200K drive
64 = /dev/fd?h420 5.25" 420K in a 1200K drive
24 = /dev/fd?h720 5.25" 720K in a 1200K drive
80 = /dev/fd?h880 5.25" 880K in a 1200K drive(1)
8 = /dev/fd?h1200 5.25" 1200K in a 1200K drive(1)
40 = /dev/fd?h1440 5.25" 1440K in a 1200K drive(1)
56 = /dev/fd?h1476 5.25" 1476K in a 1200K drive
72 = /dev/fd?h1494 5.25" 1494K in a 1200K drive
92 = /dev/fd?h1600 5.25" 1600K in a 1200K drive(1)
12 = /dev/fd?u360 3.5" 360K Double Density(2)
16 = /dev/fd?u720 3.5" 720K Double Density(1)
120 = /dev/fd?u800 3.5" 800K Double Density(2)
52 = /dev/fd?u820 3.5" 820K Double Density
68 = /dev/fd?u830 3.5" 830K Double Density
84 = /dev/fd?u1040 3.5" 1040K Double Density(1)
88 = /dev/fd?u1120 3.5" 1120K Double Density(1)
28 = /dev/fd?u1440 3.5" 1440K High Density(1)
124 = /dev/fd?u1600 3.5" 1600K High Density(1)
44 = /dev/fd?u1680 3.5" 1680K High Density(3)
60 = /dev/fd?u1722 3.5" 1722K High Density
76 = /dev/fd?u1743 3.5" 1743K High Density
96 = /dev/fd?u1760 3.5" 1760K High Density
116 = /dev/fd?u1840 3.5" 1840K High Density(3)
100 = /dev/fd?u1920 3.5" 1920K High Density(1)
32 = /dev/fd?u2880 3.5" 2880K Extra Density(1)
104 = /dev/fd?u3200 3.5" 3200K Extra Density
108 = /dev/fd?u3520 3.5" 3520K Extra Density
112 = /dev/fd?u3840 3.5" 3840K Extra Density(1)
36 = /dev/fd?CompaQ Compaq 2880K drive; obsolete?
(1) Autodetectable format
(2) Autodetectable format in a Double Density (720K) drive only
(3) Autodetectable format in a High Density (1440K) drive only
NOTE: The letter in the device name (d, q, h or u)
signifies the type of drive: 5.25" Double Density (d),
5.25" Quad Density (q), 5.25" High Density (h) or 3.5"
(any model, u). The use of the capital letters D, H
and E for the 3.5" models have been deprecated, since
the drive type is insignificant for these devices.
3 char Pseudo-TTY slaves
0 = /dev/ttyp0 First PTY slave
1 = /dev/ttyp1 Second PTY slave
...
255 = /dev/ttyef 256th PTY slave
These are the old-style (BSD) PTY devices; Unix98
devices are on major 136 and above.
3 block First MFM, RLL and IDE hard disk/CD-ROM interface
0 = /dev/hda Master: whole disk (or CD-ROM)
64 = /dev/hdb Slave: whole disk (or CD-ROM)
For partitions, add to the whole disk device number:
0 = /dev/hd? Whole disk
1 = /dev/hd?1 First partition
2 = /dev/hd?2 Second partition
...
63 = /dev/hd?63 63rd partition
For Linux/i386, partitions 1-4 are the primary
partitions, and 5 and above are logical partitions.
Other versions of Linux use partitioning schemes
appropriate to their respective architectures.
4 char TTY devices
0 = /dev/tty0 Current virtual console
1 = /dev/tty1 First virtual console
...
63 = /dev/tty63 63rd virtual console
64 = /dev/ttyS0 First UART serial port
...
255 = /dev/ttyS191 192nd UART serial port
UART serial ports refer to 8250/16450/16550 series devices.
Older versions of the Linux kernel used this major
number for BSD PTY devices. As of Linux 2.1.115, this
is no longer supported. Use major numbers 2 and 3.
4 block Aliases for dynamically allocated major devices to be used
when its not possible to create the real device nodes
because the root filesystem is mounted read-only.
0 = /dev/root
5 char Alternate TTY devices
0 = /dev/tty Current TTY device
1 = /dev/console System console
2 = /dev/ptmx PTY master multiplex
3 = /dev/ttyprintk User messages via printk TTY device
64 = /dev/cua0 Callout device for ttyS0
...
255 = /dev/cua191 Callout device for ttyS191
(5,1) is /dev/console starting with Linux 2.1.71. See
the section on terminal devices for more information
on /dev/console.
6 char Parallel printer devices
0 = /dev/lp0 Parallel printer on parport0
1 = /dev/lp1 Parallel printer on parport1
...
Current Linux kernels no longer have a fixed mapping
between parallel ports and I/O addresses. Instead,
they are redirected through the parport multiplex layer.
7 char Virtual console capture devices
0 = /dev/vcs Current vc text (glyph) contents
1 = /dev/vcs1 tty1 text (glyph) contents
...
63 = /dev/vcs63 tty63 text (glyph) contents
64 = /dev/vcsu Current vc text (unicode) contents
65 = /dev/vcsu1 tty1 text (unicode) contents
...
127 = /dev/vcsu63 tty63 text (unicode) contents
128 = /dev/vcsa Current vc text/attribute (glyph) contents
129 = /dev/vcsa1 tty1 text/attribute (glyph) contents
...
191 = /dev/vcsa63 tty63 text/attribute (glyph) contents
NOTE: These devices permit both read and write access.
7 block Loopback devices
0 = /dev/loop0 First loop device
1 = /dev/loop1 Second loop device
...
The loop devices are used to mount filesystems not
associated with block devices. The binding to the
loop devices is handled by mount(8) or losetup(8).
8 block SCSI disk devices (0-15)
0 = /dev/sda First SCSI disk whole disk
16 = /dev/sdb Second SCSI disk whole disk
32 = /dev/sdc Third SCSI disk whole disk
...
240 = /dev/sdp Sixteenth SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
9 char SCSI tape devices
0 = /dev/st0 First SCSI tape, mode 0
1 = /dev/st1 Second SCSI tape, mode 0
...
32 = /dev/st0l First SCSI tape, mode 1
33 = /dev/st1l Second SCSI tape, mode 1
...
64 = /dev/st0m First SCSI tape, mode 2
65 = /dev/st1m Second SCSI tape, mode 2
...
96 = /dev/st0a First SCSI tape, mode 3
97 = /dev/st1a Second SCSI tape, mode 3
...
128 = /dev/nst0 First SCSI tape, mode 0, no rewind
129 = /dev/nst1 Second SCSI tape, mode 0, no rewind
...
160 = /dev/nst0l First SCSI tape, mode 1, no rewind
161 = /dev/nst1l Second SCSI tape, mode 1, no rewind
...
192 = /dev/nst0m First SCSI tape, mode 2, no rewind
193 = /dev/nst1m Second SCSI tape, mode 2, no rewind
...
224 = /dev/nst0a First SCSI tape, mode 3, no rewind
225 = /dev/nst1a Second SCSI tape, mode 3, no rewind
...
"No rewind" refers to the omission of the default
automatic rewind on device close. The MTREW or MTOFFL
ioctl()'s can be used to rewind the tape regardless of
the device used to access it.
9 block Metadisk (RAID) devices
0 = /dev/md0 First metadisk group
1 = /dev/md1 Second metadisk group
...
The metadisk driver is used to span a
filesystem across multiple physical disks.
10 char Non-serial mice, misc features
0 = /dev/logibm Logitech bus mouse
1 = /dev/psaux PS/2-style mouse port
2 = /dev/inportbm Microsoft Inport bus mouse
3 = /dev/atibm ATI XL bus mouse
4 = /dev/jbm J-mouse
4 = /dev/amigamouse Amiga mouse (68k/Amiga)
5 = /dev/atarimouse Atari mouse
6 = /dev/sunmouse Sun mouse
7 = /dev/amigamouse1 Second Amiga mouse
8 = /dev/smouse Simple serial mouse driver
9 = /dev/pc110pad IBM PC-110 digitizer pad
10 = /dev/adbmouse Apple Desktop Bus mouse
11 = /dev/vrtpanel Vr41xx embedded touch panel
13 = /dev/vpcmouse Connectix Virtual PC Mouse
14 = /dev/touchscreen/ucb1x00 UCB 1x00 touchscreen
15 = /dev/touchscreen/mk712 MK712 touchscreen
128 = /dev/beep Fancy beep device
129 =
130 = /dev/watchdog Watchdog timer port
131 = /dev/temperature Machine internal temperature
132 = /dev/hwtrap Hardware fault trap
133 = /dev/exttrp External device trap
134 = /dev/apm_bios Advanced Power Management BIOS
135 = /dev/rtc Real Time Clock
137 = /dev/vhci Bluetooth virtual HCI driver
139 = /dev/openprom SPARC OpenBoot PROM
140 = /dev/relay8 Berkshire Products Octal relay card
141 = /dev/relay16 Berkshire Products ISO-16 relay card
142 =
143 = /dev/pciconf PCI configuration space
144 = /dev/nvram Non-volatile configuration RAM
145 = /dev/hfmodem Soundcard shortwave modem control
146 = /dev/graphics Linux/SGI graphics device
147 = /dev/opengl Linux/SGI OpenGL pipe
148 = /dev/gfx Linux/SGI graphics effects device
149 = /dev/input/mouse Linux/SGI Irix emulation mouse
150 = /dev/input/keyboard Linux/SGI Irix emulation keyboard
151 = /dev/led Front panel LEDs
152 = /dev/kpoll Kernel Poll Driver
153 = /dev/mergemem Memory merge device
154 = /dev/pmu Macintosh PowerBook power manager
155 =
156 = /dev/lcd Front panel LCD display
157 = /dev/ac Applicom Intl Profibus card
158 = /dev/nwbutton Netwinder external button
159 = /dev/nwdebug Netwinder debug interface
160 = /dev/nwflash Netwinder flash memory
161 = /dev/userdma User-space DMA access
162 = /dev/smbus System Management Bus
163 = /dev/lik Logitech Internet Keyboard
164 = /dev/ipmo Intel Intelligent Platform Management
165 = /dev/vmmon VMware virtual machine monitor
166 = /dev/i2o/ctl I2O configuration manager
167 = /dev/specialix_sxctl Specialix serial control
168 = /dev/tcldrv Technology Concepts serial control
169 = /dev/specialix_rioctl Specialix RIO serial control
170 = /dev/thinkpad/thinkpad IBM Thinkpad devices
171 = /dev/srripc QNX4 API IPC manager
172 = /dev/usemaclone Semaphore clone device
173 = /dev/ipmikcs Intelligent Platform Management
174 = /dev/uctrl SPARCbook 3 microcontroller
175 = /dev/agpgart AGP Graphics Address Remapping Table
176 = /dev/gtrsc Gorgy Timing radio clock
177 = /dev/cbm Serial CBM bus
178 = /dev/jsflash JavaStation OS flash SIMM
179 = /dev/xsvc High-speed shared-mem/semaphore service
180 = /dev/vrbuttons Vr41xx button input device
181 = /dev/toshiba Toshiba laptop SMM support
182 = /dev/perfctr Performance-monitoring counters
183 = /dev/hwrng Generic random number generator
184 = /dev/cpu/microcode CPU microcode update interface
186 = /dev/atomicps Atomic snapshot of process state data
187 = /dev/irnet IrNET device
188 = /dev/smbusbios SMBus BIOS
189 = /dev/ussp_ctl User space serial port control
190 = /dev/crash Mission Critical Linux crash dump facility
191 = /dev/pcl181 <information missing>
192 = /dev/nas_xbus NAS xbus LCD/buttons access
193 = /dev/d7s SPARC 7-segment display
194 = /dev/zkshim Zero-Knowledge network shim control
195 = /dev/elographics/e2201 Elographics touchscreen E271-2201
196 = /dev/vfio/vfio VFIO userspace driver interface
197 = /dev/pxa3xx-gcu PXA3xx graphics controller unit driver
198 = /dev/sexec Signed executable interface
199 = /dev/scanners/cuecat :CueCat barcode scanner
200 = /dev/net/tun TAP/TUN network device
201 = /dev/button/gulpb Transmeta GULP-B buttons
202 = /dev/emd/ctl Enhanced Metadisk RAID (EMD) control
203 = /dev/cuse Cuse (character device in user-space)
204 = /dev/video/em8300 EM8300 DVD decoder control
205 = /dev/video/em8300_mv EM8300 DVD decoder video
206 = /dev/video/em8300_ma EM8300 DVD decoder audio
207 = /dev/video/em8300_sp EM8300 DVD decoder subpicture
208 = /dev/compaq/cpqphpc Compaq PCI Hot Plug Controller
209 = /dev/compaq/cpqrid Compaq Remote Insight Driver
210 = /dev/impi/bt IMPI coprocessor block transfer
211 = /dev/impi/smic IMPI coprocessor stream interface
212 = /dev/watchdogs/0 First watchdog device
213 = /dev/watchdogs/1 Second watchdog device
214 = /dev/watchdogs/2 Third watchdog device
215 = /dev/watchdogs/3 Fourth watchdog device
216 = /dev/fujitsu/apanel Fujitsu/Siemens application panel
217 = /dev/ni/natmotn National Instruments Motion
218 = /dev/kchuid Inter-process chuid control
219 = /dev/modems/mwave MWave modem firmware upload
220 = /dev/mptctl Message passing technology (MPT) control
221 = /dev/mvista/hssdsi Montavista PICMG hot swap system driver
222 = /dev/mvista/hasi Montavista PICMG high availability
223 = /dev/input/uinput User level driver support for input
224 = /dev/tpm TCPA TPM driver
225 = /dev/pps Pulse Per Second driver
226 = /dev/systrace Systrace device
227 = /dev/mcelog X86_64 Machine Check Exception driver
228 = /dev/hpet HPET driver
229 = /dev/fuse Fuse (virtual filesystem in user-space)
230 = /dev/midishare MidiShare driver
231 = /dev/snapshot System memory snapshot device
232 = /dev/kvm Kernel-based virtual machine (hardware virtualization extensions)
233 = /dev/kmview View-OS A process with a view
234 = /dev/btrfs-control Btrfs control device
235 = /dev/autofs Autofs control device
236 = /dev/mapper/control Device-Mapper control device
237 = /dev/loop-control Loopback control device
238 = /dev/vhost-net Host kernel accelerator for virtio net
239 = /dev/uhid User-space I/O driver support for HID subsystem
240 = /dev/userio Serio driver testing device
241 = /dev/vhost-vsock Host kernel driver for virtio vsock
242 = /dev/rfkill Turning off radio transmissions (rfkill)
243-254 Reserved for local use
255 Reserved for MISC_DYNAMIC_MINOR
11 char Raw keyboard device (Linux/SPARC only)
0 = /dev/kbd Raw keyboard device
11 char Serial Mux device (Linux/PA-RISC only)
0 = /dev/ttyB0 First mux port
1 = /dev/ttyB1 Second mux port
...
11 block SCSI CD-ROM devices
0 = /dev/scd0 First SCSI CD-ROM
1 = /dev/scd1 Second SCSI CD-ROM
...
The prefix /dev/sr (instead of /dev/scd) has been deprecated.
12 char QIC-02 tape
2 = /dev/ntpqic11 QIC-11, no rewind-on-close
3 = /dev/tpqic11 QIC-11, rewind-on-close
4 = /dev/ntpqic24 QIC-24, no rewind-on-close
5 = /dev/tpqic24 QIC-24, rewind-on-close
6 = /dev/ntpqic120 QIC-120, no rewind-on-close
7 = /dev/tpqic120 QIC-120, rewind-on-close
8 = /dev/ntpqic150 QIC-150, no rewind-on-close
9 = /dev/tpqic150 QIC-150, rewind-on-close
The device names specified are proposed -- if there
are "standard" names for these devices, please let me know.
12 block
13 char Input core
0 = /dev/input/js0 First joystick
1 = /dev/input/js1 Second joystick
...
32 = /dev/input/mouse0 First mouse
33 = /dev/input/mouse1 Second mouse
...
63 = /dev/input/mice Unified mouse
64 = /dev/input/event0 First event queue
65 = /dev/input/event1 Second event queue
...
Each device type has 5 bits (32 minors).
13 block Previously used for the XT disk (/dev/xdN)
Deleted in kernel v3.9.
14 char Open Sound System (OSS)
0 = /dev/mixer Mixer control
1 = /dev/sequencer Audio sequencer
2 = /dev/midi00 First MIDI port
3 = /dev/dsp Digital audio
4 = /dev/audio Sun-compatible digital audio
6 =
7 = /dev/audioctl SPARC audio control device
8 = /dev/sequencer2 Sequencer -- alternate device
16 = /dev/mixer1 Second soundcard mixer control
17 = /dev/patmgr0 Sequencer patch manager
18 = /dev/midi01 Second MIDI port
19 = /dev/dsp1 Second soundcard digital audio
20 = /dev/audio1 Second soundcard Sun digital audio
33 = /dev/patmgr1 Sequencer patch manager
34 = /dev/midi02 Third MIDI port
50 = /dev/midi03 Fourth MIDI port
14 block
15 char Joystick
0 = /dev/js0 First analog joystick
1 = /dev/js1 Second analog joystick
...
128 = /dev/djs0 First digital joystick
129 = /dev/djs1 Second digital joystick
...
15 block Sony CDU-31A/CDU-33A CD-ROM
0 = /dev/sonycd Sony CDU-31a CD-ROM
16 char Non-SCSI scanners
0 = /dev/gs4500 Genius 4500 handheld scanner
16 block GoldStar CD-ROM
0 = /dev/gscd GoldStar CD-ROM
17 char OBSOLETE (was Chase serial card)
0 = /dev/ttyH0 First Chase port
1 = /dev/ttyH1 Second Chase port
...
17 block Optics Storage CD-ROM
0 = /dev/optcd Optics Storage CD-ROM
18 char OBSOLETE (was Chase serial card - alternate devices)
0 = /dev/cuh0 Callout device for ttyH0
1 = /dev/cuh1 Callout device for ttyH1
...
18 block Sanyo CD-ROM
0 = /dev/sjcd Sanyo CD-ROM
19 block "Double" compressed disk
0 = /dev/double0 First compressed disk
...
7 = /dev/double7 Eighth compressed disk
128 = /dev/cdouble0 Mirror of first compressed disk
...
135 = /dev/cdouble7 Mirror of eighth compressed disk
See the Double documentation for the meaning of the
mirror devices.
20 block Hitachi CD-ROM (under development)
0 = /dev/hitcd Hitachi CD-ROM
21 char Generic SCSI access
0 = /dev/sg0 First generic SCSI device
1 = /dev/sg1 Second generic SCSI device
...
Most distributions name these /dev/sga, /dev/sgb...;
this sets an unnecessary limit of 26 SCSI devices in
the system and is counter to standard Linux
device-naming practice.
21 block Acorn MFM hard drive interface
0 = /dev/mfma First MFM drive whole disk
64 = /dev/mfmb Second MFM drive whole disk
This device is used on the ARM-based Acorn RiscPC.
Partitions are handled the same way as for IDE disks
(see major number 3).
22 char Digiboard serial card
0 = /dev/ttyD0 First Digiboard port
1 = /dev/ttyD1 Second Digiboard port
...
22 block Second IDE hard disk/CD-ROM interface
0 = /dev/hdc Master: whole disk (or CD-ROM)
64 = /dev/hdd Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
23 char Digiboard serial card - alternate devices
0 = /dev/cud0 Callout device for ttyD0
1 = /dev/cud1 Callout device for ttyD1
...
23 block Mitsumi proprietary CD-ROM
0 = /dev/mcd Mitsumi CD-ROM
24 char Stallion serial card
0 = /dev/ttyE0 Stallion port 0 card 0
1 = /dev/ttyE1 Stallion port 1 card 0
...
64 = /dev/ttyE64 Stallion port 0 card 1
65 = /dev/ttyE65 Stallion port 1 card 1
...
128 = /dev/ttyE128 Stallion port 0 card 2
129 = /dev/ttyE129 Stallion port 1 card 2
...
192 = /dev/ttyE192 Stallion port 0 card 3
193 = /dev/ttyE193 Stallion port 1 card 3
...
24 block Sony CDU-535 CD-ROM
0 = /dev/cdu535 Sony CDU-535 CD-ROM
25 char Stallion serial card - alternate devices
0 = /dev/cue0 Callout device for ttyE0
1 = /dev/cue1 Callout device for ttyE1
...
64 = /dev/cue64 Callout device for ttyE64
65 = /dev/cue65 Callout device for ttyE65
...
128 = /dev/cue128 Callout device for ttyE128
129 = /dev/cue129 Callout device for ttyE129
...
192 = /dev/cue192 Callout device for ttyE192
193 = /dev/cue193 Callout device for ttyE193
...
25 block First Matsushita (Panasonic/SoundBlaster) CD-ROM
0 = /dev/sbpcd0 Panasonic CD-ROM controller 0 unit 0
1 = /dev/sbpcd1 Panasonic CD-ROM controller 0 unit 1
2 = /dev/sbpcd2 Panasonic CD-ROM controller 0 unit 2
3 = /dev/sbpcd3 Panasonic CD-ROM controller 0 unit 3
26 char
26 block Second Matsushita (Panasonic/SoundBlaster) CD-ROM
0 = /dev/sbpcd4 Panasonic CD-ROM controller 1 unit 0
1 = /dev/sbpcd5 Panasonic CD-ROM controller 1 unit 1
2 = /dev/sbpcd6 Panasonic CD-ROM controller 1 unit 2
3 = /dev/sbpcd7 Panasonic CD-ROM controller 1 unit 3
27 char QIC-117 tape
0 = /dev/qft0 Unit 0, rewind-on-close
1 = /dev/qft1 Unit 1, rewind-on-close
2 = /dev/qft2 Unit 2, rewind-on-close
3 = /dev/qft3 Unit 3, rewind-on-close
4 = /dev/nqft0 Unit 0, no rewind-on-close
5 = /dev/nqft1 Unit 1, no rewind-on-close
6 = /dev/nqft2 Unit 2, no rewind-on-close
7 = /dev/nqft3 Unit 3, no rewind-on-close
16 = /dev/zqft0 Unit 0, rewind-on-close, compression
17 = /dev/zqft1 Unit 1, rewind-on-close, compression
18 = /dev/zqft2 Unit 2, rewind-on-close, compression
19 = /dev/zqft3 Unit 3, rewind-on-close, compression
20 = /dev/nzqft0 Unit 0, no rewind-on-close, compression
21 = /dev/nzqft1 Unit 1, no rewind-on-close, compression
22 = /dev/nzqft2 Unit 2, no rewind-on-close, compression
23 = /dev/nzqft3 Unit 3, no rewind-on-close, compression
32 = /dev/rawqft0 Unit 0, rewind-on-close, no file marks
33 = /dev/rawqft1 Unit 1, rewind-on-close, no file marks
34 = /dev/rawqft2 Unit 2, rewind-on-close, no file marks
35 = /dev/rawqft3 Unit 3, rewind-on-close, no file marks
36 = /dev/nrawqft0 Unit 0, no rewind-on-close, no file marks
37 = /dev/nrawqft1 Unit 1, no rewind-on-close, no file marks
38 = /dev/nrawqft2 Unit 2, no rewind-on-close, no file marks
39 = /dev/nrawqft3 Unit 3, no rewind-on-close, no file marks
27 block Third Matsushita (Panasonic/SoundBlaster) CD-ROM
0 = /dev/sbpcd8 Panasonic CD-ROM controller 2 unit 0
1 = /dev/sbpcd9 Panasonic CD-ROM controller 2 unit 1
2 = /dev/sbpcd10 Panasonic CD-ROM controller 2 unit 2
3 = /dev/sbpcd11 Panasonic CD-ROM controller 2 unit 3
28 char Stallion serial card - card programming
0 = /dev/staliomem0 First Stallion card I/O memory
1 = /dev/staliomem1 Second Stallion card I/O memory
2 = /dev/staliomem2 Third Stallion card I/O memory
3 = /dev/staliomem3 Fourth Stallion card I/O memory
28 char Atari SLM ACSI laser printer (68k/Atari)
0 = /dev/slm0 First SLM laser printer
1 = /dev/slm1 Second SLM laser printer
...
28 block Fourth Matsushita (Panasonic/SoundBlaster) CD-ROM
0 = /dev/sbpcd12 Panasonic CD-ROM controller 3 unit 0
1 = /dev/sbpcd13 Panasonic CD-ROM controller 3 unit 1
2 = /dev/sbpcd14 Panasonic CD-ROM controller 3 unit 2
3 = /dev/sbpcd15 Panasonic CD-ROM controller 3 unit 3
28 block ACSI disk (68k/Atari)
0 = /dev/ada First ACSI disk whole disk
16 = /dev/adb Second ACSI disk whole disk
32 = /dev/adc Third ACSI disk whole disk
...
240 = /dev/adp 16th ACSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15, like SCSI.
29 char Universal frame buffer
0 = /dev/fb0 First frame buffer
1 = /dev/fb1 Second frame buffer
...
31 = /dev/fb31 32nd frame buffer
29 block Aztech/Orchid/Okano/Wearnes CD-ROM
0 = /dev/aztcd Aztech CD-ROM
30 char iBCS-2 compatibility devices
0 = /dev/socksys Socket access
1 = /dev/spx SVR3 local X interface
32 = /dev/inet/ip Network access
33 = /dev/inet/icmp
34 = /dev/inet/ggp
35 = /dev/inet/ipip
36 = /dev/inet/tcp
37 = /dev/inet/egp
38 = /dev/inet/pup
39 = /dev/inet/udp
40 = /dev/inet/idp
41 = /dev/inet/rawip
Additionally, iBCS-2 requires the following links:
/dev/ip -> /dev/inet/ip
/dev/icmp -> /dev/inet/icmp
/dev/ggp -> /dev/inet/ggp
/dev/ipip -> /dev/inet/ipip
/dev/tcp -> /dev/inet/tcp
/dev/egp -> /dev/inet/egp
/dev/pup -> /dev/inet/pup
/dev/udp -> /dev/inet/udp
/dev/idp -> /dev/inet/idp
/dev/rawip -> /dev/inet/rawip
/dev/inet/arp -> /dev/inet/udp
/dev/inet/rip -> /dev/inet/udp
/dev/nfsd -> /dev/socksys
/dev/X0R -> /dev/null (? apparently not required ?)
30 block Philips LMS CM-205 CD-ROM
0 = /dev/cm205cd Philips LMS CM-205 CD-ROM
/dev/lmscd is an older name for this device. This
driver does not work with the CM-205MS CD-ROM.
31 char MPU-401 MIDI
0 = /dev/mpu401data MPU-401 data port
1 = /dev/mpu401stat MPU-401 status port
31 block ROM/flash memory card
0 = /dev/rom0 First ROM card (rw)
...
7 = /dev/rom7 Eighth ROM card (rw)
8 = /dev/rrom0 First ROM card (ro)
...
15 = /dev/rrom7 Eighth ROM card (ro)
16 = /dev/flash0 First flash memory card (rw)
...
23 = /dev/flash7 Eighth flash memory card (rw)
24 = /dev/rflash0 First flash memory card (ro)
...
31 = /dev/rflash7 Eighth flash memory card (ro)
The read-write (rw) devices support back-caching
written data in RAM, as well as writing to flash RAM
devices. The read-only devices (ro) support reading
only.
32 char Specialix serial card
0 = /dev/ttyX0 First Specialix port
1 = /dev/ttyX1 Second Specialix port
...
32 block Philips LMS CM-206 CD-ROM
0 = /dev/cm206cd Philips LMS CM-206 CD-ROM
33 char Specialix serial card - alternate devices
0 = /dev/cux0 Callout device for ttyX0
1 = /dev/cux1 Callout device for ttyX1
...
33 block Third IDE hard disk/CD-ROM interface
0 = /dev/hde Master: whole disk (or CD-ROM)
64 = /dev/hdf Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
34 char Z8530 HDLC driver
0 = /dev/scc0 First Z8530, first port
1 = /dev/scc1 First Z8530, second port
2 = /dev/scc2 Second Z8530, first port
3 = /dev/scc3 Second Z8530, second port
...
In a previous version these devices were named
/dev/sc1 for /dev/scc0, /dev/sc2 for /dev/scc1, and so
on.
34 block Fourth IDE hard disk/CD-ROM interface
0 = /dev/hdg Master: whole disk (or CD-ROM)
64 = /dev/hdh Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
35 char tclmidi MIDI driver
0 = /dev/midi0 First MIDI port, kernel timed
1 = /dev/midi1 Second MIDI port, kernel timed
2 = /dev/midi2 Third MIDI port, kernel timed
3 = /dev/midi3 Fourth MIDI port, kernel timed
64 = /dev/rmidi0 First MIDI port, untimed
65 = /dev/rmidi1 Second MIDI port, untimed
66 = /dev/rmidi2 Third MIDI port, untimed
67 = /dev/rmidi3 Fourth MIDI port, untimed
128 = /dev/smpte0 First MIDI port, SMPTE timed
129 = /dev/smpte1 Second MIDI port, SMPTE timed
130 = /dev/smpte2 Third MIDI port, SMPTE timed
131 = /dev/smpte3 Fourth MIDI port, SMPTE timed
35 block Slow memory ramdisk
0 = /dev/slram Slow memory ramdisk
36 char Netlink support
0 = /dev/route Routing, device updates, kernel to user
1 = /dev/skip enSKIP security cache control
3 = /dev/fwmonitor Firewall packet copies
16 = /dev/tap0 First Ethertap device
...
31 = /dev/tap15 16th Ethertap device
36 block OBSOLETE (was MCA ESDI hard disk)
37 char IDE tape
0 = /dev/ht0 First IDE tape
1 = /dev/ht1 Second IDE tape
...
128 = /dev/nht0 First IDE tape, no rewind-on-close
129 = /dev/nht1 Second IDE tape, no rewind-on-close
...
Currently, only one IDE tape drive is supported.
37 block Zorro II ramdisk
0 = /dev/z2ram Zorro II ramdisk
38 char Myricom PCI Myrinet board
0 = /dev/mlanai0 First Myrinet board
1 = /dev/mlanai1 Second Myrinet board
...
This device is used for status query, board control
and "user level packet I/O." This board is also
accessible as a standard networking "eth" device.
38 block OBSOLETE (was Linux/AP+)
39 char ML-16P experimental I/O board
0 = /dev/ml16pa-a0 First card, first analog channel
1 = /dev/ml16pa-a1 First card, second analog channel
...
15 = /dev/ml16pa-a15 First card, 16th analog channel
16 = /dev/ml16pa-d First card, digital lines
17 = /dev/ml16pa-c0 First card, first counter/timer
18 = /dev/ml16pa-c1 First card, second counter/timer
19 = /dev/ml16pa-c2 First card, third counter/timer
32 = /dev/ml16pb-a0 Second card, first analog channel
33 = /dev/ml16pb-a1 Second card, second analog channel
...
47 = /dev/ml16pb-a15 Second card, 16th analog channel
48 = /dev/ml16pb-d Second card, digital lines
49 = /dev/ml16pb-c0 Second card, first counter/timer
50 = /dev/ml16pb-c1 Second card, second counter/timer
51 = /dev/ml16pb-c2 Second card, third counter/timer
...
39 block
40 char
40 block
41 char Yet Another Micro Monitor
0 = /dev/yamm Yet Another Micro Monitor
41 block
42 char Demo/sample use
42 block Demo/sample use
This number is intended for use in sample code, as
well as a general "example" device number. It
should never be used for a device driver that is being
distributed; either obtain an official number or use
the local/experimental range. The sudden addition or
removal of a driver with this number should not cause
ill effects to the system (bugs excepted.)
IN PARTICULAR, ANY DISTRIBUTION WHICH CONTAINS A
DEVICE DRIVER USING MAJOR NUMBER 42 IS NONCOMPLIANT.
43 char isdn4linux virtual modem
0 = /dev/ttyI0 First virtual modem
...
63 = /dev/ttyI63 64th virtual modem
43 block Network block devices
0 = /dev/nb0 First network block device
1 = /dev/nb1 Second network block device
...
Network Block Device is somehow similar to loopback
devices: If you read from it, it sends packet across
network asking server for data. If you write to it, it
sends packet telling server to write. It could be used
to mounting filesystems over the net, swapping over
the net, implementing block device in userland etc.
44 char isdn4linux virtual modem - alternate devices
0 = /dev/cui0 Callout device for ttyI0
...
63 = /dev/cui63 Callout device for ttyI63
44 block Flash Translation Layer (FTL) filesystems
0 = /dev/ftla FTL on first Memory Technology Device
16 = /dev/ftlb FTL on second Memory Technology Device
32 = /dev/ftlc FTL on third Memory Technology Device
...
240 = /dev/ftlp FTL on 16th Memory Technology Device
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the partition
limit is 15 rather than 63 per disk (same as SCSI.)
45 char isdn4linux ISDN BRI driver
0 = /dev/isdn0 First virtual B channel raw data
...
63 = /dev/isdn63 64th virtual B channel raw data
64 = /dev/isdnctrl0 First channel control/debug
...
127 = /dev/isdnctrl63 64th channel control/debug
128 = /dev/ippp0 First SyncPPP device
...
191 = /dev/ippp63 64th SyncPPP device
255 = /dev/isdninfo ISDN monitor interface
45 block Parallel port IDE disk devices
0 = /dev/pda First parallel port IDE disk
16 = /dev/pdb Second parallel port IDE disk
32 = /dev/pdc Third parallel port IDE disk
48 = /dev/pdd Fourth parallel port IDE disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the partition
limit is 15 rather than 63 per disk.
46 char Comtrol Rocketport serial card
0 = /dev/ttyR0 First Rocketport port
1 = /dev/ttyR1 Second Rocketport port
...
46 block Parallel port ATAPI CD-ROM devices
0 = /dev/pcd0 First parallel port ATAPI CD-ROM
1 = /dev/pcd1 Second parallel port ATAPI CD-ROM
2 = /dev/pcd2 Third parallel port ATAPI CD-ROM
3 = /dev/pcd3 Fourth parallel port ATAPI CD-ROM
47 char Comtrol Rocketport serial card - alternate devices
0 = /dev/cur0 Callout device for ttyR0
1 = /dev/cur1 Callout device for ttyR1
...
47 block Parallel port ATAPI disk devices
0 = /dev/pf0 First parallel port ATAPI disk
1 = /dev/pf1 Second parallel port ATAPI disk
2 = /dev/pf2 Third parallel port ATAPI disk
3 = /dev/pf3 Fourth parallel port ATAPI disk
This driver is intended for floppy disks and similar
devices and hence does not support partitioning.
48 char SDL RISCom serial card
0 = /dev/ttyL0 First RISCom port
1 = /dev/ttyL1 Second RISCom port
...
48 block Mylex DAC960 PCI RAID controller; first controller
0 = /dev/rd/c0d0 First disk, whole disk
8 = /dev/rd/c0d1 Second disk, whole disk
...
248 = /dev/rd/c0d31 32nd disk, whole disk
For partitions add:
0 = /dev/rd/c?d? Whole disk
1 = /dev/rd/c?d?p1 First partition
...
7 = /dev/rd/c?d?p7 Seventh partition
49 char SDL RISCom serial card - alternate devices
0 = /dev/cul0 Callout device for ttyL0
1 = /dev/cul1 Callout device for ttyL1
...
49 block Mylex DAC960 PCI RAID controller; second controller
0 = /dev/rd/c1d0 First disk, whole disk
8 = /dev/rd/c1d1 Second disk, whole disk
...
248 = /dev/rd/c1d31 32nd disk, whole disk
Partitions are handled as for major 48.
50 char Reserved for GLINT
50 block Mylex DAC960 PCI RAID controller; third controller
0 = /dev/rd/c2d0 First disk, whole disk
8 = /dev/rd/c2d1 Second disk, whole disk
...
248 = /dev/rd/c2d31 32nd disk, whole disk
51 char Baycom radio modem OR Radio Tech BIM-XXX-RS232 radio modem
0 = /dev/bc0 First Baycom radio modem
1 = /dev/bc1 Second Baycom radio modem
...
51 block Mylex DAC960 PCI RAID controller; fourth controller
0 = /dev/rd/c3d0 First disk, whole disk
8 = /dev/rd/c3d1 Second disk, whole disk
...
248 = /dev/rd/c3d31 32nd disk, whole disk
Partitions are handled as for major 48.
52 char Spellcaster DataComm/BRI ISDN card
0 = /dev/dcbri0 First DataComm card
1 = /dev/dcbri1 Second DataComm card
2 = /dev/dcbri2 Third DataComm card
3 = /dev/dcbri3 Fourth DataComm card
52 block Mylex DAC960 PCI RAID controller; fifth controller
0 = /dev/rd/c4d0 First disk, whole disk
8 = /dev/rd/c4d1 Second disk, whole disk
...
248 = /dev/rd/c4d31 32nd disk, whole disk
Partitions are handled as for major 48.
53 char BDM interface for remote debugging MC683xx microcontrollers
0 = /dev/pd_bdm0 PD BDM interface on lp0
1 = /dev/pd_bdm1 PD BDM interface on lp1
2 = /dev/pd_bdm2 PD BDM interface on lp2
4 = /dev/icd_bdm0 ICD BDM interface on lp0
5 = /dev/icd_bdm1 ICD BDM interface on lp1
6 = /dev/icd_bdm2 ICD BDM interface on lp2
This device is used for the interfacing to the MC683xx
microcontrollers via Background Debug Mode by use of a
Parallel Port interface. PD is the Motorola Public
Domain Interface and ICD is the commercial interface
by P&E.
53 block Mylex DAC960 PCI RAID controller; sixth controller
0 = /dev/rd/c5d0 First disk, whole disk
8 = /dev/rd/c5d1 Second disk, whole disk
...
248 = /dev/rd/c5d31 32nd disk, whole disk
Partitions are handled as for major 48.
54 char Electrocardiognosis Holter serial card
0 = /dev/holter0 First Holter port
1 = /dev/holter1 Second Holter port
2 = /dev/holter2 Third Holter port
A custom serial card used by Electrocardiognosis SRL
<mseritan@ottonel.pub.ro> to transfer data from Holter
24-hour heart monitoring equipment.
54 block Mylex DAC960 PCI RAID controller; seventh controller
0 = /dev/rd/c6d0 First disk, whole disk
8 = /dev/rd/c6d1 Second disk, whole disk
...
248 = /dev/rd/c6d31 32nd disk, whole disk
Partitions are handled as for major 48.
55 char DSP56001 digital signal processor
0 = /dev/dsp56k First DSP56001
55 block Mylex DAC960 PCI RAID controller; eighth controller
0 = /dev/rd/c7d0 First disk, whole disk
8 = /dev/rd/c7d1 Second disk, whole disk
...
248 = /dev/rd/c7d31 32nd disk, whole disk
Partitions are handled as for major 48.
56 char Apple Desktop Bus
0 = /dev/adb ADB bus control
Additional devices will be added to this number, all
starting with /dev/adb.
56 block Fifth IDE hard disk/CD-ROM interface
0 = /dev/hdi Master: whole disk (or CD-ROM)
64 = /dev/hdj Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
57 char Hayes ESP serial card
0 = /dev/ttyP0 First ESP port
1 = /dev/ttyP1 Second ESP port
...
57 block Sixth IDE hard disk/CD-ROM interface
0 = /dev/hdk Master: whole disk (or CD-ROM)
64 = /dev/hdl Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
58 char Hayes ESP serial card - alternate devices
0 = /dev/cup0 Callout device for ttyP0
1 = /dev/cup1 Callout device for ttyP1
...
58 block Reserved for logical volume manager
59 char sf firewall package
0 = /dev/firewall Communication with sf kernel module
59 block Generic PDA filesystem device
0 = /dev/pda0 First PDA device
1 = /dev/pda1 Second PDA device
...
The pda devices are used to mount filesystems on
remote pda's (basically slow handheld machines with
proprietary OS's and limited memory and storage
running small fs translation drivers) through serial /
IRDA / parallel links.
NAMING CONFLICT -- PROPOSED REVISED NAME /dev/rpda0 etc
60-63 char LOCAL/EXPERIMENTAL USE
60-63 block LOCAL/EXPERIMENTAL USE
Allocated for local/experimental use. For devices not
assigned official numbers, these ranges should be
used in order to avoid conflicting with future assignments.
64 char ENskip kernel encryption package
0 = /dev/enskip Communication with ENskip kernel module
64 block Scramdisk/DriveCrypt encrypted devices
0 = /dev/scramdisk/master Master node for ioctls
1 = /dev/scramdisk/1 First encrypted device
2 = /dev/scramdisk/2 Second encrypted device
...
255 = /dev/scramdisk/255 255th encrypted device
The filename of the encrypted container and the passwords
are sent via ioctls (using the sdmount tool) to the master
node which then activates them via one of the
/dev/scramdisk/x nodes for loop mounting (all handled
through the sdmount tool).
Requested by: andy@scramdisklinux.org
65 char Sundance "plink" Transputer boards (obsolete, unused)
0 = /dev/plink0 First plink device
1 = /dev/plink1 Second plink device
2 = /dev/plink2 Third plink device
3 = /dev/plink3 Fourth plink device
64 = /dev/rplink0 First plink device, raw
65 = /dev/rplink1 Second plink device, raw
66 = /dev/rplink2 Third plink device, raw
67 = /dev/rplink3 Fourth plink device, raw
128 = /dev/plink0d First plink device, debug
129 = /dev/plink1d Second plink device, debug
130 = /dev/plink2d Third plink device, debug
131 = /dev/plink3d Fourth plink device, debug
192 = /dev/rplink0d First plink device, raw, debug
193 = /dev/rplink1d Second plink device, raw, debug
194 = /dev/rplink2d Third plink device, raw, debug
195 = /dev/rplink3d Fourth plink device, raw, debug
This is a commercial driver; contact James Howes
<jth@prosig.demon.co.uk> for information.
65 block SCSI disk devices (16-31)
0 = /dev/sdq 17th SCSI disk whole disk
16 = /dev/sdr 18th SCSI disk whole disk
32 = /dev/sds 19th SCSI disk whole disk
...
240 = /dev/sdaf 32nd SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
66 char YARC PowerPC PCI coprocessor card
0 = /dev/yppcpci0 First YARC card
1 = /dev/yppcpci1 Second YARC card
...
66 block SCSI disk devices (32-47)
0 = /dev/sdag 33th SCSI disk whole disk
16 = /dev/sdah 34th SCSI disk whole disk
32 = /dev/sdai 35th SCSI disk whole disk
...
240 = /dev/sdav 48nd SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
67 char Coda network file system
0 = /dev/cfs0 Coda cache manager
See http://www.coda.cs.cmu.edu for information about Coda.
67 block SCSI disk devices (48-63)
0 = /dev/sdaw 49th SCSI disk whole disk
16 = /dev/sdax 50th SCSI disk whole disk
32 = /dev/sday 51st SCSI disk whole disk
...
240 = /dev/sdbl 64th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
68 char CAPI 2.0 interface
0 = /dev/capi20 Control device
1 = /dev/capi20.00 First CAPI 2.0 application
2 = /dev/capi20.01 Second CAPI 2.0 application
...
20 = /dev/capi20.19 19th CAPI 2.0 application
ISDN CAPI 2.0 driver for use with CAPI 2.0
applications; currently supports the AVM B1 card.
68 block SCSI disk devices (64-79)
0 = /dev/sdbm 65th SCSI disk whole disk
16 = /dev/sdbn 66th SCSI disk whole disk
32 = /dev/sdbo 67th SCSI disk whole disk
...
240 = /dev/sdcb 80th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
69 char MA16 numeric accelerator card
0 = /dev/ma16 Board memory access
69 block SCSI disk devices (80-95)
0 = /dev/sdcc 81st SCSI disk whole disk
16 = /dev/sdcd 82nd SCSI disk whole disk
32 = /dev/sdce 83th SCSI disk whole disk
...
240 = /dev/sdcr 96th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
70 char SpellCaster Protocol Services Interface
0 = /dev/apscfg Configuration interface
1 = /dev/apsauth Authentication interface
2 = /dev/apslog Logging interface
3 = /dev/apsdbg Debugging interface
64 = /dev/apsisdn ISDN command interface
65 = /dev/apsasync Async command interface
128 = /dev/apsmon Monitor interface
70 block SCSI disk devices (96-111)
0 = /dev/sdcs 97th SCSI disk whole disk
16 = /dev/sdct 98th SCSI disk whole disk
32 = /dev/sdcu 99th SCSI disk whole disk
...
240 = /dev/sddh 112nd SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
71 char Computone IntelliPort II serial card
0 = /dev/ttyF0 IntelliPort II board 0, port 0
1 = /dev/ttyF1 IntelliPort II board 0, port 1
...
63 = /dev/ttyF63 IntelliPort II board 0, port 63
64 = /dev/ttyF64 IntelliPort II board 1, port 0
65 = /dev/ttyF65 IntelliPort II board 1, port 1
...
127 = /dev/ttyF127 IntelliPort II board 1, port 63
128 = /dev/ttyF128 IntelliPort II board 2, port 0
129 = /dev/ttyF129 IntelliPort II board 2, port 1
...
191 = /dev/ttyF191 IntelliPort II board 2, port 63
192 = /dev/ttyF192 IntelliPort II board 3, port 0
193 = /dev/ttyF193 IntelliPort II board 3, port 1
...
255 = /dev/ttyF255 IntelliPort II board 3, port 63
71 block SCSI disk devices (112-127)
0 = /dev/sddi 113th SCSI disk whole disk
16 = /dev/sddj 114th SCSI disk whole disk
32 = /dev/sddk 115th SCSI disk whole disk
...
240 = /dev/sddx 128th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
72 char Computone IntelliPort II serial card - alternate devices
0 = /dev/cuf0 Callout device for ttyF0
1 = /dev/cuf1 Callout device for ttyF1
...
63 = /dev/cuf63 Callout device for ttyF63
64 = /dev/cuf64 Callout device for ttyF64
65 = /dev/cuf65 Callout device for ttyF65
...
127 = /dev/cuf127 Callout device for ttyF127
128 = /dev/cuf128 Callout device for ttyF128
129 = /dev/cuf129 Callout device for ttyF129
...
191 = /dev/cuf191 Callout device for ttyF191
192 = /dev/cuf192 Callout device for ttyF192
193 = /dev/cuf193 Callout device for ttyF193
...
255 = /dev/cuf255 Callout device for ttyF255
72 block Compaq Intelligent Drive Array, first controller
0 = /dev/ida/c0d0 First logical drive whole disk
16 = /dev/ida/c0d1 Second logical drive whole disk
...
240 = /dev/ida/c0d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
73 char Computone IntelliPort II serial card - control devices
0 = /dev/ip2ipl0 Loadware device for board 0
1 = /dev/ip2stat0 Status device for board 0
4 = /dev/ip2ipl1 Loadware device for board 1
5 = /dev/ip2stat1 Status device for board 1
8 = /dev/ip2ipl2 Loadware device for board 2
9 = /dev/ip2stat2 Status device for board 2
12 = /dev/ip2ipl3 Loadware device for board 3
13 = /dev/ip2stat3 Status device for board 3
73 block Compaq Intelligent Drive Array, second controller
0 = /dev/ida/c1d0 First logical drive whole disk
16 = /dev/ida/c1d1 Second logical drive whole disk
...
240 = /dev/ida/c1d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
74 char SCI bridge
0 = /dev/SCI/0 SCI device 0
1 = /dev/SCI/1 SCI device 1
...
Currently for Dolphin Interconnect Solutions' PCI-SCI
bridge.
74 block Compaq Intelligent Drive Array, third controller
0 = /dev/ida/c2d0 First logical drive whole disk
16 = /dev/ida/c2d1 Second logical drive whole disk
...
240 = /dev/ida/c2d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
75 char Specialix IO8+ serial card
0 = /dev/ttyW0 First IO8+ port, first card
1 = /dev/ttyW1 Second IO8+ port, first card
...
8 = /dev/ttyW8 First IO8+ port, second card
...
75 block Compaq Intelligent Drive Array, fourth controller
0 = /dev/ida/c3d0 First logical drive whole disk
16 = /dev/ida/c3d1 Second logical drive whole disk
...
240 = /dev/ida/c3d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
76 char Specialix IO8+ serial card - alternate devices
0 = /dev/cuw0 Callout device for ttyW0
1 = /dev/cuw1 Callout device for ttyW1
...
8 = /dev/cuw8 Callout device for ttyW8
...
76 block Compaq Intelligent Drive Array, fifth controller
0 = /dev/ida/c4d0 First logical drive whole disk
16 = /dev/ida/c4d1 Second logical drive whole disk
...
240 = /dev/ida/c4d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
77 char ComScire Quantum Noise Generator
0 = /dev/qng ComScire Quantum Noise Generator
77 block Compaq Intelligent Drive Array, sixth controller
0 = /dev/ida/c5d0 First logical drive whole disk
16 = /dev/ida/c5d1 Second logical drive whole disk
...
240 = /dev/ida/c5d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
78 char PAM Software's multimodem boards
0 = /dev/ttyM0 First PAM modem
1 = /dev/ttyM1 Second PAM modem
...
78 block Compaq Intelligent Drive Array, seventh controller
0 = /dev/ida/c6d0 First logical drive whole disk
16 = /dev/ida/c6d1 Second logical drive whole disk
...
240 = /dev/ida/c6d15 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
79 char PAM Software's multimodem boards - alternate devices
0 = /dev/cum0 Callout device for ttyM0
1 = /dev/cum1 Callout device for ttyM1
...
79 block Compaq Intelligent Drive Array, eighth controller
0 = /dev/ida/c7d0 First logical drive whole disk
16 = /dev/ida/c7d1 Second logical drive whole disk
...
240 = /dev/ida/c715 16th logical drive whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
80 char Photometrics AT200 CCD camera
0 = /dev/at200 Photometrics AT200 CCD camera
80 block I2O hard disk
0 = /dev/i2o/hda First I2O hard disk, whole disk
16 = /dev/i2o/hdb Second I2O hard disk, whole disk
...
240 = /dev/i2o/hdp 16th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
81 char video4linux
0 = /dev/video0 Video capture/overlay device
...
63 = /dev/video63 Video capture/overlay device
64 = /dev/radio0 Radio device
...
127 = /dev/radio63 Radio device
128 = /dev/swradio0 Software Defined Radio device
...
191 = /dev/swradio63 Software Defined Radio device
224 = /dev/vbi0 Vertical blank interrupt
...
255 = /dev/vbi31 Vertical blank interrupt
Minor numbers are allocated dynamically unless
CONFIG_VIDEO_FIXED_MINOR_RANGES (default n)
configuration option is set.
81 block I2O hard disk
0 = /dev/i2o/hdq 17th I2O hard disk, whole disk
16 = /dev/i2o/hdr 18th I2O hard disk, whole disk
...
240 = /dev/i2o/hdaf 32nd I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
82 char WiNRADiO communications receiver card
0 = /dev/winradio0 First WiNRADiO card
1 = /dev/winradio1 Second WiNRADiO card
...
The driver and documentation may be obtained from
https://www.winradio.com/
82 block I2O hard disk
0 = /dev/i2o/hdag 33rd I2O hard disk, whole disk
16 = /dev/i2o/hdah 34th I2O hard disk, whole disk
...
240 = /dev/i2o/hdav 48th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
83 char Matrox mga_vid video driver
0 = /dev/mga_vid0 1st video card
1 = /dev/mga_vid1 2nd video card
2 = /dev/mga_vid2 3rd video card
...
15 = /dev/mga_vid15 16th video card
83 block I2O hard disk
0 = /dev/i2o/hdaw 49th I2O hard disk, whole disk
16 = /dev/i2o/hdax 50th I2O hard disk, whole disk
...
240 = /dev/i2o/hdbl 64th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
84 char Ikon 1011[57] Versatec Greensheet Interface
0 = /dev/ihcp0 First Greensheet port
1 = /dev/ihcp1 Second Greensheet port
84 block I2O hard disk
0 = /dev/i2o/hdbm 65th I2O hard disk, whole disk
16 = /dev/i2o/hdbn 66th I2O hard disk, whole disk
...
240 = /dev/i2o/hdcb 80th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
85 char Linux/SGI shared memory input queue
0 = /dev/shmiq Master shared input queue
1 = /dev/qcntl0 First device pushed
2 = /dev/qcntl1 Second device pushed
...
85 block I2O hard disk
0 = /dev/i2o/hdcc 81st I2O hard disk, whole disk
16 = /dev/i2o/hdcd 82nd I2O hard disk, whole disk
...
240 = /dev/i2o/hdcr 96th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
86 char SCSI media changer
0 = /dev/sch0 First SCSI media changer
1 = /dev/sch1 Second SCSI media changer
...
86 block I2O hard disk
0 = /dev/i2o/hdcs 97th I2O hard disk, whole disk
16 = /dev/i2o/hdct 98th I2O hard disk, whole disk
...
240 = /dev/i2o/hddh 112th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
87 char Sony Control-A1 stereo control bus
0 = /dev/controla0 First device on chain
1 = /dev/controla1 Second device on chain
...
87 block I2O hard disk
0 = /dev/i2o/hddi 113rd I2O hard disk, whole disk
16 = /dev/i2o/hddj 114th I2O hard disk, whole disk
...
240 = /dev/i2o/hddx 128th I2O hard disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
88 char COMX synchronous serial card
0 = /dev/comx0 COMX channel 0
1 = /dev/comx1 COMX channel 1
...
88 block Seventh IDE hard disk/CD-ROM interface
0 = /dev/hdm Master: whole disk (or CD-ROM)
64 = /dev/hdn Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
89 char I2C bus interface
0 = /dev/i2c-0 First I2C adapter
1 = /dev/i2c-1 Second I2C adapter
...
89 block Eighth IDE hard disk/CD-ROM interface
0 = /dev/hdo Master: whole disk (or CD-ROM)
64 = /dev/hdp Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
90 char Memory Technology Device (RAM, ROM, Flash)
0 = /dev/mtd0 First MTD (rw)
1 = /dev/mtdr0 First MTD (ro)
...
30 = /dev/mtd15 16th MTD (rw)
31 = /dev/mtdr15 16th MTD (ro)
90 block Ninth IDE hard disk/CD-ROM interface
0 = /dev/hdq Master: whole disk (or CD-ROM)
64 = /dev/hdr Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
91 char CAN-Bus devices
0 = /dev/can0 First CAN-Bus controller
1 = /dev/can1 Second CAN-Bus controller
...
91 block Tenth IDE hard disk/CD-ROM interface
0 = /dev/hds Master: whole disk (or CD-ROM)
64 = /dev/hdt Slave: whole disk (or CD-ROM)
Partitions are handled the same way as for the first
interface (see major number 3).
92 char Reserved for ith Kommunikationstechnik MIC ISDN card
92 block PPDD encrypted disk driver
0 = /dev/ppdd0 First encrypted disk
1 = /dev/ppdd1 Second encrypted disk
...
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
93 char
93 block NAND Flash Translation Layer filesystem
0 = /dev/nftla First NFTL layer
16 = /dev/nftlb Second NFTL layer
...
240 = /dev/nftlp 16th NTFL layer
94 char
94 block IBM S/390 DASD block storage
0 = /dev/dasda First DASD device, major
1 = /dev/dasda1 First DASD device, block 1
2 = /dev/dasda2 First DASD device, block 2
3 = /dev/dasda3 First DASD device, block 3
4 = /dev/dasdb Second DASD device, major
5 = /dev/dasdb1 Second DASD device, block 1
6 = /dev/dasdb2 Second DASD device, block 2
7 = /dev/dasdb3 Second DASD device, block 3
...
95 char IP filter
0 = /dev/ipl Filter control device/log file
1 = /dev/ipnat NAT control device/log file
2 = /dev/ipstate State information log file
3 = /dev/ipauth Authentication control device/log file
...
96 char Parallel port ATAPI tape devices
0 = /dev/pt0 First parallel port ATAPI tape
1 = /dev/pt1 Second parallel port ATAPI tape
...
128 = /dev/npt0 First p.p. ATAPI tape, no rewind
129 = /dev/npt1 Second p.p. ATAPI tape, no rewind
...
96 block Inverse NAND Flash Translation Layer
0 = /dev/inftla First INFTL layer
16 = /dev/inftlb Second INFTL layer
...
240 = /dev/inftlp 16th INTFL layer
97 char Parallel port generic ATAPI interface
0 = /dev/pg0 First parallel port ATAPI device
1 = /dev/pg1 Second parallel port ATAPI device
2 = /dev/pg2 Third parallel port ATAPI device
3 = /dev/pg3 Fourth parallel port ATAPI device
These devices support the same API as the generic SCSI
devices.
98 char Control and Measurement Device (comedi)
0 = /dev/comedi0 First comedi device
1 = /dev/comedi1 Second comedi device
...
47 = /dev/comedi47 48th comedi device
Minors 48 to 255 are reserved for comedi subdevices with
pathnames of the form "/dev/comediX_subdY", where "X" is the
minor number of the associated comedi device and "Y" is the
subdevice number. These subdevice minors are assigned
dynamically, so there is no fixed mapping from subdevice
pathnames to minor numbers.
See https://www.comedi.org/ for information about the Comedi
project.
98 block User-mode virtual block device
0 = /dev/ubda First user-mode block device
16 = /dev/ubdb Second user-mode block device
...
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
This device is used by the user-mode virtual kernel port.
99 char Raw parallel ports
0 = /dev/parport0 First parallel port
1 = /dev/parport1 Second parallel port
...
99 block JavaStation flash disk
0 = /dev/jsfd JavaStation flash disk
100 char Telephony for Linux
0 = /dev/phone0 First telephony device
1 = /dev/phone1 Second telephony device
...
101 char Motorola DSP 56xxx board
0 = /dev/mdspstat Status information
1 = /dev/mdsp1 First DSP board I/O controls
...
16 = /dev/mdsp16 16th DSP board I/O controls
101 block AMI HyperDisk RAID controller
0 = /dev/amiraid/ar0 First array whole disk
16 = /dev/amiraid/ar1 Second array whole disk
...
240 = /dev/amiraid/ar15 16th array whole disk
For each device, partitions are added as:
0 = /dev/amiraid/ar? Whole disk
1 = /dev/amiraid/ar?p1 First partition
2 = /dev/amiraid/ar?p2 Second partition
...
15 = /dev/amiraid/ar?p15 15th partition
102 char
102 block Compressed block device
0 = /dev/cbd/a First compressed block device, whole device
16 = /dev/cbd/b Second compressed block device, whole device
...
240 = /dev/cbd/p 16th compressed block device, whole device
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
103 char Arla network file system
0 = /dev/nnpfs0 First NNPFS device
1 = /dev/nnpfs1 Second NNPFS device
Arla is a free clone of the Andrew File System, AFS.
The NNPFS device gives user mode filesystem
implementations a kernel presence for caching and easy
mounting. For more information about the project,
write to <arla-drinkers@stacken.kth.se> or see
https://www.stacken.kth.se/project/arla/
103 block Audit device
0 = /dev/audit Audit device
104 char Flash BIOS support
104 block Compaq Next Generation Drive Array, first controller
0 = /dev/cciss/c0d0 First logical drive, whole disk
16 = /dev/cciss/c0d1 Second logical drive, whole disk
...
240 = /dev/cciss/c0d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
105 char Comtrol VS-1000 serial controller
0 = /dev/ttyV0 First VS-1000 port
1 = /dev/ttyV1 Second VS-1000 port
...
105 block Compaq Next Generation Drive Array, second controller
0 = /dev/cciss/c1d0 First logical drive, whole disk
16 = /dev/cciss/c1d1 Second logical drive, whole disk
...
240 = /dev/cciss/c1d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
106 char Comtrol VS-1000 serial controller - alternate devices
0 = /dev/cuv0 First VS-1000 port
1 = /dev/cuv1 Second VS-1000 port
...
106 block Compaq Next Generation Drive Array, third controller
0 = /dev/cciss/c2d0 First logical drive, whole disk
16 = /dev/cciss/c2d1 Second logical drive, whole disk
...
240 = /dev/cciss/c2d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
107 char 3Dfx Voodoo Graphics device
0 = /dev/3dfx Primary 3Dfx graphics device
107 block Compaq Next Generation Drive Array, fourth controller
0 = /dev/cciss/c3d0 First logical drive, whole disk
16 = /dev/cciss/c3d1 Second logical drive, whole disk
...
240 = /dev/cciss/c3d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
108 char Device independent PPP interface
0 = /dev/ppp Device independent PPP interface
108 block Compaq Next Generation Drive Array, fifth controller
0 = /dev/cciss/c4d0 First logical drive, whole disk
16 = /dev/cciss/c4d1 Second logical drive, whole disk
...
240 = /dev/cciss/c4d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
109 char Reserved for logical volume manager
109 block Compaq Next Generation Drive Array, sixth controller
0 = /dev/cciss/c5d0 First logical drive, whole disk
16 = /dev/cciss/c5d1 Second logical drive, whole disk
...
240 = /dev/cciss/c5d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
110 char miroMEDIA Surround board
0 = /dev/srnd0 First miroMEDIA Surround board
1 = /dev/srnd1 Second miroMEDIA Surround board
...
110 block Compaq Next Generation Drive Array, seventh controller
0 = /dev/cciss/c6d0 First logical drive, whole disk
16 = /dev/cciss/c6d1 Second logical drive, whole disk
...
240 = /dev/cciss/c6d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
111 char
111 block Compaq Next Generation Drive Array, eighth controller
0 = /dev/cciss/c7d0 First logical drive, whole disk
16 = /dev/cciss/c7d1 Second logical drive, whole disk
...
240 = /dev/cciss/c7d15 16th logical drive, whole disk
Partitions are handled the same way as for Mylex
DAC960 (see major number 48) except that the limit on
partitions is 15.
112 char ISI serial card
0 = /dev/ttyM0 First ISI port
1 = /dev/ttyM1 Second ISI port
...
There is currently a device-naming conflict between
these and PAM multimodems (major 78).
112 block IBM iSeries virtual disk
0 = /dev/iseries/vda First virtual disk, whole disk
8 = /dev/iseries/vdb Second virtual disk, whole disk
...
200 = /dev/iseries/vdz 26th virtual disk, whole disk
208 = /dev/iseries/vdaa 27th virtual disk, whole disk
...
248 = /dev/iseries/vdaf 32nd virtual disk, whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 7.
113 char ISI serial card - alternate devices
0 = /dev/cum0 Callout device for ttyM0
1 = /dev/cum1 Callout device for ttyM1
...
113 block IBM iSeries virtual CD-ROM
0 = /dev/iseries/vcda First virtual CD-ROM
1 = /dev/iseries/vcdb Second virtual CD-ROM
...
114 char Picture Elements ISE board
0 = /dev/ise0 First ISE board
1 = /dev/ise1 Second ISE board
...
128 = /dev/isex0 Control node for first ISE board
129 = /dev/isex1 Control node for second ISE board
...
The ISE board is an embedded computer, optimized for
image processing. The /dev/iseN nodes are the general
I/O access to the board, the /dev/isex0 nodes command
nodes used to control the board.
114 block IDE BIOS powered software RAID interfaces such as the
Promise Fastrak
0 = /dev/ataraid/d0
1 = /dev/ataraid/d0p1
2 = /dev/ataraid/d0p2
...
16 = /dev/ataraid/d1
17 = /dev/ataraid/d1p1
18 = /dev/ataraid/d1p2
...
255 = /dev/ataraid/d15p15
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
115 char TI link cable devices (115 was formerly the console driver speaker)
0 = /dev/tipar0 Parallel cable on first parallel port
...
7 = /dev/tipar7 Parallel cable on seventh parallel port
8 = /dev/tiser0 Serial cable on first serial port
...
15 = /dev/tiser7 Serial cable on seventh serial port
16 = /dev/tiusb0 First USB cable
...
47 = /dev/tiusb31 32nd USB cable
115 block NetWare (NWFS) Devices (0-255)
The NWFS (NetWare) devices are used to present a
collection of NetWare Mirror Groups or NetWare
Partitions as a logical storage segment for
use in mounting NetWare volumes. A maximum of
256 NetWare volumes can be supported in a single
machine.
http://cgfa.telepac.pt/ftp2/kernel.org/linux/kernel/people/jmerkey/nwfs/
0 = /dev/nwfs/v0 First NetWare (NWFS) Logical Volume
1 = /dev/nwfs/v1 Second NetWare (NWFS) Logical Volume
2 = /dev/nwfs/v2 Third NetWare (NWFS) Logical Volume
...
255 = /dev/nwfs/v255 Last NetWare (NWFS) Logical Volume
116 char Advanced Linux Sound Driver (ALSA)
116 block MicroMemory battery backed RAM adapter (NVRAM)
Supports 16 boards, 15 partitions each.
Requested by neilb at cse.unsw.edu.au.
0 = /dev/umem/d0 Whole of first board
1 = /dev/umem/d0p1 First partition of first board
2 = /dev/umem/d0p2 Second partition of first board
15 = /dev/umem/d0p15 15th partition of first board
16 = /dev/umem/d1 Whole of second board
17 = /dev/umem/d1p1 First partition of second board
...
255= /dev/umem/d15p15 15th partition of 16th board.
117 char COSA/SRP synchronous serial card
0 = /dev/cosa0c0 1st board, 1st channel
1 = /dev/cosa0c1 1st board, 2nd channel
...
16 = /dev/cosa1c0 2nd board, 1st channel
17 = /dev/cosa1c1 2nd board, 2nd channel
...
117 block Enterprise Volume Management System (EVMS)
The EVMS driver uses a layered, plug-in model to provide
unparalleled flexibility and extensibility in managing
storage. This allows for easy expansion or customization
of various levels of volume management. Requested by
Mark Peloquin (peloquin at us.ibm.com).
Note: EVMS populates and manages all the devnodes in
/dev/evms.
http://sf.net/projects/evms
0 = /dev/evms/block_device EVMS block device
1 = /dev/evms/legacyname1 First EVMS legacy device
2 = /dev/evms/legacyname2 Second EVMS legacy device
...
Both ranges can grow (down or up) until they meet.
...
254 = /dev/evms/EVMSname2 Second EVMS native device
255 = /dev/evms/EVMSname1 First EVMS native device
Note: legacyname(s) are derived from the normal legacy
device names. For example, /dev/hda5 would become
/dev/evms/hda5.
118 char IBM Cryptographic Accelerator
0 = /dev/ica Virtual interface to all IBM Crypto Accelerators
1 = /dev/ica0 IBMCA Device 0
2 = /dev/ica1 IBMCA Device 1
...
119 char VMware virtual network control
0 = /dev/vnet0 1st virtual network
1 = /dev/vnet1 2nd virtual network
...
120-127 char LOCAL/EXPERIMENTAL USE
120-127 block LOCAL/EXPERIMENTAL USE
Allocated for local/experimental use. For devices not
assigned official numbers, these ranges should be
used in order to avoid conflicting with future assignments.
128-135 char Unix98 PTY masters
These devices should not have corresponding device
nodes; instead they should be accessed through the
/dev/ptmx cloning interface.
128 block SCSI disk devices (128-143)
0 = /dev/sddy 129th SCSI disk whole disk
16 = /dev/sddz 130th SCSI disk whole disk
32 = /dev/sdea 131th SCSI disk whole disk
...
240 = /dev/sden 144th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
129 block SCSI disk devices (144-159)
0 = /dev/sdeo 145th SCSI disk whole disk
16 = /dev/sdep 146th SCSI disk whole disk
32 = /dev/sdeq 147th SCSI disk whole disk
...
240 = /dev/sdfd 160th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
130 char (Misc devices)
130 block SCSI disk devices (160-175)
0 = /dev/sdfe 161st SCSI disk whole disk
16 = /dev/sdff 162nd SCSI disk whole disk
32 = /dev/sdfg 163rd SCSI disk whole disk
...
240 = /dev/sdft 176th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
131 block SCSI disk devices (176-191)
0 = /dev/sdfu 177th SCSI disk whole disk
16 = /dev/sdfv 178th SCSI disk whole disk
32 = /dev/sdfw 179th SCSI disk whole disk
...
240 = /dev/sdgj 192nd SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
132 block SCSI disk devices (192-207)
0 = /dev/sdgk 193rd SCSI disk whole disk
16 = /dev/sdgl 194th SCSI disk whole disk
32 = /dev/sdgm 195th SCSI disk whole disk
...
240 = /dev/sdgz 208th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
133 block SCSI disk devices (208-223)
0 = /dev/sdha 209th SCSI disk whole disk
16 = /dev/sdhb 210th SCSI disk whole disk
32 = /dev/sdhc 211th SCSI disk whole disk
...
240 = /dev/sdhp 224th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
134 block SCSI disk devices (224-239)
0 = /dev/sdhq 225th SCSI disk whole disk
16 = /dev/sdhr 226th SCSI disk whole disk
32 = /dev/sdhs 227th SCSI disk whole disk
...
240 = /dev/sdif 240th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
135 block SCSI disk devices (240-255)
0 = /dev/sdig 241st SCSI disk whole disk
16 = /dev/sdih 242nd SCSI disk whole disk
32 = /dev/sdih 243rd SCSI disk whole disk
...
240 = /dev/sdiv 256th SCSI disk whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
136-143 char Unix98 PTY slaves
0 = /dev/pts/0 First Unix98 pseudo-TTY
1 = /dev/pts/1 Second Unix98 pseudo-TTY
...
These device nodes are automatically generated with
the proper permissions and modes by mounting the
devpts filesystem onto /dev/pts with the appropriate
mount options (distribution dependent, however, on
*most* distributions the appropriate options are
"mode=0620,gid=<gid of the "tty" group>".)
136 block Mylex DAC960 PCI RAID controller; ninth controller
0 = /dev/rd/c8d0 First disk, whole disk
8 = /dev/rd/c8d1 Second disk, whole disk
...
248 = /dev/rd/c8d31 32nd disk, whole disk
Partitions are handled as for major 48.
137 block Mylex DAC960 PCI RAID controller; tenth controller
0 = /dev/rd/c9d0 First disk, whole disk
8 = /dev/rd/c9d1 Second disk, whole disk
...
248 = /dev/rd/c9d31 32nd disk, whole disk
Partitions are handled as for major 48.
138 block Mylex DAC960 PCI RAID controller; eleventh controller
0 = /dev/rd/c10d0 First disk, whole disk
8 = /dev/rd/c10d1 Second disk, whole disk
...
248 = /dev/rd/c10d31 32nd disk, whole disk
Partitions are handled as for major 48.
139 block Mylex DAC960 PCI RAID controller; twelfth controller
0 = /dev/rd/c11d0 First disk, whole disk
8 = /dev/rd/c11d1 Second disk, whole disk
...
248 = /dev/rd/c11d31 32nd disk, whole disk
Partitions are handled as for major 48.
140 block Mylex DAC960 PCI RAID controller; thirteenth controller
0 = /dev/rd/c12d0 First disk, whole disk
8 = /dev/rd/c12d1 Second disk, whole disk
...
248 = /dev/rd/c12d31 32nd disk, whole disk
Partitions are handled as for major 48.
141 block Mylex DAC960 PCI RAID controller; fourteenth controller
0 = /dev/rd/c13d0 First disk, whole disk
8 = /dev/rd/c13d1 Second disk, whole disk
...
248 = /dev/rd/c13d31 32nd disk, whole disk
Partitions are handled as for major 48.
142 block Mylex DAC960 PCI RAID controller; fifteenth controller
0 = /dev/rd/c14d0 First disk, whole disk
8 = /dev/rd/c14d1 Second disk, whole disk
...
248 = /dev/rd/c14d31 32nd disk, whole disk
Partitions are handled as for major 48.
143 block Mylex DAC960 PCI RAID controller; sixteenth controller
0 = /dev/rd/c15d0 First disk, whole disk
8 = /dev/rd/c15d1 Second disk, whole disk
...
248 = /dev/rd/c15d31 32nd disk, whole disk
Partitions are handled as for major 48.
144 char Encapsulated PPP
0 = /dev/pppox0 First PPP over Ethernet
...
63 = /dev/pppox63 64th PPP over Ethernet
This is primarily used for ADSL.
The SST 5136-DN DeviceNet interface driver has been
relocated to major 183 due to an unfortunate conflict.
144 block Expansion Area #1 for more non-device (e.g. NFS) mounts
0 = mounted device 256
255 = mounted device 511
145 char SAM9407-based soundcard
0 = /dev/sam0_mixer
1 = /dev/sam0_sequencer
2 = /dev/sam0_midi00
3 = /dev/sam0_dsp
4 = /dev/sam0_audio
6 = /dev/sam0_sndstat
18 = /dev/sam0_midi01
34 = /dev/sam0_midi02
50 = /dev/sam0_midi03
64 = /dev/sam1_mixer
...
128 = /dev/sam2_mixer
...
192 = /dev/sam3_mixer
...
Device functions match OSS, but offer a number of
addons, which are sam9407 specific. OSS can be
operated simultaneously, taking care of the codec.
145 block Expansion Area #2 for more non-device (e.g. NFS) mounts
0 = mounted device 512
255 = mounted device 767
146 char SYSTRAM SCRAMNet mirrored-memory network
0 = /dev/scramnet0 First SCRAMNet device
1 = /dev/scramnet1 Second SCRAMNet device
...
146 block Expansion Area #3 for more non-device (e.g. NFS) mounts
0 = mounted device 768
255 = mounted device 1023
147 char Aureal Semiconductor Vortex Audio device
0 = /dev/aureal0 First Aureal Vortex
1 = /dev/aureal1 Second Aureal Vortex
...
147 block Distributed Replicated Block Device (DRBD)
0 = /dev/drbd0 First DRBD device
1 = /dev/drbd1 Second DRBD device
...
148 char Technology Concepts serial card
0 = /dev/ttyT0 First TCL port
1 = /dev/ttyT1 Second TCL port
...
149 char Technology Concepts serial card - alternate devices
0 = /dev/cut0 Callout device for ttyT0
1 = /dev/cut0 Callout device for ttyT1
...
150 char Real-Time Linux FIFOs
0 = /dev/rtf0 First RTLinux FIFO
1 = /dev/rtf1 Second RTLinux FIFO
...
151 char DPT I2O SmartRaid V controller
0 = /dev/dpti0 First DPT I2O adapter
1 = /dev/dpti1 Second DPT I2O adapter
...
152 char EtherDrive Control Device
0 = /dev/etherd/ctl Connect/Disconnect an EtherDrive
1 = /dev/etherd/err Monitor errors
2 = /dev/etherd/raw Raw AoE packet monitor
152 block EtherDrive Block Devices
0 = /dev/etherd/0 EtherDrive 0
...
255 = /dev/etherd/255 EtherDrive 255
153 char SPI Bus Interface (sometimes referred to as MicroWire)
0 = /dev/spi0 First SPI device on the bus
1 = /dev/spi1 Second SPI device on the bus
...
15 = /dev/spi15 Sixteenth SPI device on the bus
153 block Enhanced Metadisk RAID (EMD) storage units
0 = /dev/emd/0 First unit
1 = /dev/emd/0p1 Partition 1 on First unit
2 = /dev/emd/0p2 Partition 2 on First unit
...
15 = /dev/emd/0p15 Partition 15 on First unit
16 = /dev/emd/1 Second unit
32 = /dev/emd/2 Third unit
...
240 = /dev/emd/15 Sixteenth unit
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
154 char Specialix RIO serial card
0 = /dev/ttySR0 First RIO port
...
255 = /dev/ttySR255 256th RIO port
155 char Specialix RIO serial card - alternate devices
0 = /dev/cusr0 Callout device for ttySR0
...
255 = /dev/cusr255 Callout device for ttySR255
156 char Specialix RIO serial card
0 = /dev/ttySR256 257th RIO port
...
255 = /dev/ttySR511 512th RIO port
157 char Specialix RIO serial card - alternate devices
0 = /dev/cusr256 Callout device for ttySR256
...
255 = /dev/cusr511 Callout device for ttySR511
158 char Dialogic GammaLink fax driver
0 = /dev/gfax0 GammaLink channel 0
1 = /dev/gfax1 GammaLink channel 1
...
159 char RESERVED
159 block RESERVED
160 char General Purpose Instrument Bus (GPIB)
0 = /dev/gpib0 First GPIB bus
1 = /dev/gpib1 Second GPIB bus
...
160 block Carmel 8-port SATA Disks on First Controller
0 = /dev/carmel/0 SATA disk 0 whole disk
1 = /dev/carmel/0p1 SATA disk 0 partition 1
...
31 = /dev/carmel/0p31 SATA disk 0 partition 31
32 = /dev/carmel/1 SATA disk 1 whole disk
64 = /dev/carmel/2 SATA disk 2 whole disk
...
224 = /dev/carmel/7 SATA disk 7 whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 31.
161 char IrCOMM devices (IrDA serial/parallel emulation)
0 = /dev/ircomm0 First IrCOMM device
1 = /dev/ircomm1 Second IrCOMM device
...
16 = /dev/irlpt0 First IrLPT device
17 = /dev/irlpt1 Second IrLPT device
...
161 block Carmel 8-port SATA Disks on Second Controller
0 = /dev/carmel/8 SATA disk 8 whole disk
1 = /dev/carmel/8p1 SATA disk 8 partition 1
...
31 = /dev/carmel/8p31 SATA disk 8 partition 31
32 = /dev/carmel/9 SATA disk 9 whole disk
64 = /dev/carmel/10 SATA disk 10 whole disk
...
224 = /dev/carmel/15 SATA disk 15 whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 31.
162 char Raw block device interface
0 = /dev/rawctl Raw I/O control device
1 = /dev/raw/raw1 First raw I/O device
2 = /dev/raw/raw2 Second raw I/O device
...
max minor number of raw device is set by kernel config
MAX_RAW_DEVS or raw module parameter 'max_raw_devs'
163 char
164 char Chase Research AT/PCI-Fast serial card
0 = /dev/ttyCH0 AT/PCI-Fast board 0, port 0
...
15 = /dev/ttyCH15 AT/PCI-Fast board 0, port 15
16 = /dev/ttyCH16 AT/PCI-Fast board 1, port 0
...
31 = /dev/ttyCH31 AT/PCI-Fast board 1, port 15
32 = /dev/ttyCH32 AT/PCI-Fast board 2, port 0
...
47 = /dev/ttyCH47 AT/PCI-Fast board 2, port 15
48 = /dev/ttyCH48 AT/PCI-Fast board 3, port 0
...
63 = /dev/ttyCH63 AT/PCI-Fast board 3, port 15
165 char Chase Research AT/PCI-Fast serial card - alternate devices
0 = /dev/cuch0 Callout device for ttyCH0
...
63 = /dev/cuch63 Callout device for ttyCH63
166 char ACM USB modems
0 = /dev/ttyACM0 First ACM modem
1 = /dev/ttyACM1 Second ACM modem
...
167 char ACM USB modems - alternate devices
0 = /dev/cuacm0 Callout device for ttyACM0
1 = /dev/cuacm1 Callout device for ttyACM1
...
168 char Eracom CSA7000 PCI encryption adaptor
0 = /dev/ecsa0 First CSA7000
1 = /dev/ecsa1 Second CSA7000
...
169 char Eracom CSA8000 PCI encryption adaptor
0 = /dev/ecsa8-0 First CSA8000
1 = /dev/ecsa8-1 Second CSA8000
...
170 char AMI MegaRAC remote access controller
0 = /dev/megarac0 First MegaRAC card
1 = /dev/megarac1 Second MegaRAC card
...
171 char Reserved for IEEE 1394 (Firewire)
172 char Moxa Intellio serial card
0 = /dev/ttyMX0 First Moxa port
1 = /dev/ttyMX1 Second Moxa port
...
127 = /dev/ttyMX127 128th Moxa port
128 = /dev/moxactl Moxa control port
173 char Moxa Intellio serial card - alternate devices
0 = /dev/cumx0 Callout device for ttyMX0
1 = /dev/cumx1 Callout device for ttyMX1
...
127 = /dev/cumx127 Callout device for ttyMX127
174 char SmartIO serial card
0 = /dev/ttySI0 First SmartIO port
1 = /dev/ttySI1 Second SmartIO port
...
175 char SmartIO serial card - alternate devices
0 = /dev/cusi0 Callout device for ttySI0
1 = /dev/cusi1 Callout device for ttySI1
...
176 char nCipher nFast PCI crypto accelerator
0 = /dev/nfastpci0 First nFast PCI device
1 = /dev/nfastpci1 First nFast PCI device
...
177 char TI PCILynx memory spaces
0 = /dev/pcilynx/aux0 AUX space of first PCILynx card
...
15 = /dev/pcilynx/aux15 AUX space of 16th PCILynx card
16 = /dev/pcilynx/rom0 ROM space of first PCILynx card
...
31 = /dev/pcilynx/rom15 ROM space of 16th PCILynx card
32 = /dev/pcilynx/ram0 RAM space of first PCILynx card
...
47 = /dev/pcilynx/ram15 RAM space of 16th PCILynx card
178 char Giganet cLAN1xxx virtual interface adapter
0 = /dev/clanvi0 First cLAN adapter
1 = /dev/clanvi1 Second cLAN adapter
...
179 block MMC block devices
0 = /dev/mmcblk0 First SD/MMC card
1 = /dev/mmcblk0p1 First partition on first MMC card
8 = /dev/mmcblk1 Second SD/MMC card
...
The start of next SD/MMC card can be configured with
CONFIG_MMC_BLOCK_MINORS, or overridden at boot/modprobe
time using the mmcblk.perdev_minors option. That would
bump the offset between each card to be the configured
value instead of the default 8.
179 char CCube DVXChip-based PCI products
0 = /dev/dvxirq0 First DVX device
1 = /dev/dvxirq1 Second DVX device
...
180 char USB devices
0 = /dev/usb/lp0 First USB printer
...
15 = /dev/usb/lp15 16th USB printer
48 = /dev/usb/scanner0 First USB scanner
...
63 = /dev/usb/scanner15 16th USB scanner
64 = /dev/usb/rio500 Diamond Rio 500
65 = /dev/usb/usblcd USBLCD Interface (info@usblcd.de)
66 = /dev/usb/cpad0 Synaptics cPad (mouse/LCD)
96 = /dev/usb/hiddev0 1st USB HID device
...
111 = /dev/usb/hiddev15 16th USB HID device
112 = /dev/usb/auer0 1st auerswald ISDN device
...
127 = /dev/usb/auer15 16th auerswald ISDN device
128 = /dev/usb/brlvgr0 First Braille Voyager device
...
131 = /dev/usb/brlvgr3 Fourth Braille Voyager device
132 = /dev/usb/idmouse ID Mouse (fingerprint scanner) device
133 = /dev/usb/sisusbvga1 First SiSUSB VGA device
...
140 = /dev/usb/sisusbvga8 Eighth SISUSB VGA device
144 = /dev/usb/lcd USB LCD device
160 = /dev/usb/legousbtower0 1st USB Legotower device
...
175 = /dev/usb/legousbtower15 16th USB Legotower device
176 = /dev/usb/usbtmc1 First USB TMC device
...
191 = /dev/usb/usbtmc16 16th USB TMC device
192 = /dev/usb/yurex1 First USB Yurex device
...
209 = /dev/usb/yurex16 16th USB Yurex device
180 block USB block devices
0 = /dev/uba First USB block device
8 = /dev/ubb Second USB block device
16 = /dev/ubc Third USB block device
...
181 char Conrad Electronic parallel port radio clocks
0 = /dev/pcfclock0 First Conrad radio clock
1 = /dev/pcfclock1 Second Conrad radio clock
...
182 char Picture Elements THR2 binarizer
0 = /dev/pethr0 First THR2 board
1 = /dev/pethr1 Second THR2 board
...
183 char SST 5136-DN DeviceNet interface
0 = /dev/ss5136dn0 First DeviceNet interface
1 = /dev/ss5136dn1 Second DeviceNet interface
...
This device used to be assigned to major number 144.
It had to be moved due to an unfortunate conflict.
184 char Picture Elements' video simulator/sender
0 = /dev/pevss0 First sender board
1 = /dev/pevss1 Second sender board
...
185 char InterMezzo high availability file system
0 = /dev/intermezzo0 First cache manager
1 = /dev/intermezzo1 Second cache manager
...
See http://web.archive.org/web/20080115195241/
http://inter-mezzo.org/index.html
186 char Object-based storage control device
0 = /dev/obd0 First obd control device
1 = /dev/obd1 Second obd control device
...
See ftp://ftp.lustre.org/pub/obd for code and information.
187 char DESkey hardware encryption device
0 = /dev/deskey0 First DES key
1 = /dev/deskey1 Second DES key
...
188 char USB serial converters
0 = /dev/ttyUSB0 First USB serial converter
1 = /dev/ttyUSB1 Second USB serial converter
...
189 char USB serial converters - alternate devices
0 = /dev/cuusb0 Callout device for ttyUSB0
1 = /dev/cuusb1 Callout device for ttyUSB1
...
190 char Kansas City tracker/tuner card
0 = /dev/kctt0 First KCT/T card
1 = /dev/kctt1 Second KCT/T card
...
191 char Reserved for PCMCIA
192 char Kernel profiling interface
0 = /dev/profile Profiling control device
1 = /dev/profile0 Profiling device for CPU 0
2 = /dev/profile1 Profiling device for CPU 1
...
193 char Kernel event-tracing interface
0 = /dev/trace Tracing control device
1 = /dev/trace0 Tracing device for CPU 0
2 = /dev/trace1 Tracing device for CPU 1
...
194 char linVideoStreams (LINVS)
0 = /dev/mvideo/status0 Video compression status
1 = /dev/mvideo/stream0 Video stream
2 = /dev/mvideo/frame0 Single compressed frame
3 = /dev/mvideo/rawframe0 Raw uncompressed frame
4 = /dev/mvideo/codec0 Direct codec access
5 = /dev/mvideo/video4linux0 Video4Linux compatibility
16 = /dev/mvideo/status1 Second device
...
32 = /dev/mvideo/status2 Third device
...
...
240 = /dev/mvideo/status15 16th device
...
195 char Nvidia graphics devices
0 = /dev/nvidia0 First Nvidia card
1 = /dev/nvidia1 Second Nvidia card
...
255 = /dev/nvidiactl Nvidia card control device
196 char Tormenta T1 card
0 = /dev/tor/0 Master control channel for all cards
1 = /dev/tor/1 First DS0
2 = /dev/tor/2 Second DS0
...
48 = /dev/tor/48 48th DS0
49 = /dev/tor/49 First pseudo-channel
50 = /dev/tor/50 Second pseudo-channel
...
197 char OpenTNF tracing facility
0 = /dev/tnf/t0 Trace 0 data extraction
1 = /dev/tnf/t1 Trace 1 data extraction
...
128 = /dev/tnf/status Tracing facility status
130 = /dev/tnf/trace Tracing device
198 char Total Impact TPMP2 quad coprocessor PCI card
0 = /dev/tpmp2/0 First card
1 = /dev/tpmp2/1 Second card
...
199 char Veritas volume manager (VxVM) volumes
0 = /dev/vx/rdsk/*/* First volume
1 = /dev/vx/rdsk/*/* Second volume
...
199 block Veritas volume manager (VxVM) volumes
0 = /dev/vx/dsk/*/* First volume
1 = /dev/vx/dsk/*/* Second volume
...
The namespace in these directories is maintained by
the user space VxVM software.
200 char Veritas VxVM configuration interface
0 = /dev/vx/config Configuration access node
1 = /dev/vx/trace Volume i/o trace access node
2 = /dev/vx/iod Volume i/o daemon access node
3 = /dev/vx/info Volume information access node
4 = /dev/vx/task Volume tasks access node
5 = /dev/vx/taskmon Volume tasks monitor daemon
201 char Veritas VxVM dynamic multipathing driver
0 = /dev/vx/rdmp/* First multipath device
1 = /dev/vx/rdmp/* Second multipath device
...
201 block Veritas VxVM dynamic multipathing driver
0 = /dev/vx/dmp/* First multipath device
1 = /dev/vx/dmp/* Second multipath device
...
The namespace in these directories is maintained by
the user space VxVM software.
202 char CPU model-specific registers
0 = /dev/cpu/0/msr MSRs on CPU 0
1 = /dev/cpu/1/msr MSRs on CPU 1
...
202 block Xen Virtual Block Device
0 = /dev/xvda First Xen VBD whole disk
16 = /dev/xvdb Second Xen VBD whole disk
32 = /dev/xvdc Third Xen VBD whole disk
...
240 = /dev/xvdp Sixteenth Xen VBD whole disk
Partitions are handled in the same way as for IDE
disks (see major number 3) except that the limit on
partitions is 15.
203 char CPU CPUID information
0 = /dev/cpu/0/cpuid CPUID on CPU 0
1 = /dev/cpu/1/cpuid CPUID on CPU 1
...
204 char Low-density serial ports
0 = /dev/ttyLU0 LinkUp Systems L72xx UART - port 0
1 = /dev/ttyLU1 LinkUp Systems L72xx UART - port 1
2 = /dev/ttyLU2 LinkUp Systems L72xx UART - port 2
3 = /dev/ttyLU3 LinkUp Systems L72xx UART - port 3
4 = /dev/ttyFB0 Intel Footbridge (ARM)
5 = /dev/ttySA0 StrongARM builtin serial port 0
6 = /dev/ttySA1 StrongARM builtin serial port 1
7 = /dev/ttySA2 StrongARM builtin serial port 2
8 = /dev/ttySC0 SCI serial port (SuperH) - port 0
9 = /dev/ttySC1 SCI serial port (SuperH) - port 1
10 = /dev/ttySC2 SCI serial port (SuperH) - port 2
11 = /dev/ttySC3 SCI serial port (SuperH) - port 3
12 = /dev/ttyFW0 Firmware console - port 0
13 = /dev/ttyFW1 Firmware console - port 1
14 = /dev/ttyFW2 Firmware console - port 2
15 = /dev/ttyFW3 Firmware console - port 3
16 = /dev/ttyAM0 ARM "AMBA" serial port 0
...
31 = /dev/ttyAM15 ARM "AMBA" serial port 15
32 = /dev/ttyDB0 DataBooster serial port 0
...
39 = /dev/ttyDB7 DataBooster serial port 7
40 = /dev/ttySG0 SGI Altix console port
41 = /dev/ttySMX0 Motorola i.MX - port 0
42 = /dev/ttySMX1 Motorola i.MX - port 1
43 = /dev/ttySMX2 Motorola i.MX - port 2
44 = /dev/ttyMM0 Marvell MPSC - port 0 (obsolete unused)
45 = /dev/ttyMM1 Marvell MPSC - port 1 (obsolete unused)
46 = /dev/ttyCPM0 PPC CPM (SCC or SMC) - port 0
...
47 = /dev/ttyCPM5 PPC CPM (SCC or SMC) - port 5
50 = /dev/ttyIOC0 Altix serial card
...
81 = /dev/ttyIOC31 Altix serial card
82 = /dev/ttyVR0 NEC VR4100 series SIU
83 = /dev/ttyVR1 NEC VR4100 series DSIU
84 = /dev/ttyIOC84 Altix ioc4 serial card
...
115 = /dev/ttyIOC115 Altix ioc4 serial card
116 = /dev/ttySIOC0 Altix ioc3 serial card
...
147 = /dev/ttySIOC31 Altix ioc3 serial card
148 = /dev/ttyPSC0 PPC PSC - port 0
...
153 = /dev/ttyPSC5 PPC PSC - port 5
154 = /dev/ttyAT0 ATMEL serial port 0
...
169 = /dev/ttyAT15 ATMEL serial port 15
170 = /dev/ttyNX0 Hilscher netX serial port 0
...
185 = /dev/ttyNX15 Hilscher netX serial port 15
186 = /dev/ttyJ0 JTAG1 DCC protocol based serial port emulation
187 = /dev/ttyUL0 Xilinx uartlite - port 0
...
190 = /dev/ttyUL3 Xilinx uartlite - port 3
191 = /dev/xvc0 Xen virtual console - port 0
192 = /dev/ttyPZ0 pmac_zilog - port 0
...
195 = /dev/ttyPZ3 pmac_zilog - port 3
196 = /dev/ttyTX0 TX39/49 serial port 0
...
204 = /dev/ttyTX7 TX39/49 serial port 7
205 = /dev/ttySC0 SC26xx serial port 0
206 = /dev/ttySC1 SC26xx serial port 1
207 = /dev/ttySC2 SC26xx serial port 2
208 = /dev/ttySC3 SC26xx serial port 3
209 = /dev/ttyMAX0 MAX3100 serial port 0
210 = /dev/ttyMAX1 MAX3100 serial port 1
211 = /dev/ttyMAX2 MAX3100 serial port 2
212 = /dev/ttyMAX3 MAX3100 serial port 3
205 char Low-density serial ports (alternate device)
0 = /dev/culu0 Callout device for ttyLU0
1 = /dev/culu1 Callout device for ttyLU1
2 = /dev/culu2 Callout device for ttyLU2
3 = /dev/culu3 Callout device for ttyLU3
4 = /dev/cufb0 Callout device for ttyFB0
5 = /dev/cusa0 Callout device for ttySA0
6 = /dev/cusa1 Callout device for ttySA1
7 = /dev/cusa2 Callout device for ttySA2
8 = /dev/cusc0 Callout device for ttySC0
9 = /dev/cusc1 Callout device for ttySC1
10 = /dev/cusc2 Callout device for ttySC2
11 = /dev/cusc3 Callout device for ttySC3
12 = /dev/cufw0 Callout device for ttyFW0
13 = /dev/cufw1 Callout device for ttyFW1
14 = /dev/cufw2 Callout device for ttyFW2
15 = /dev/cufw3 Callout device for ttyFW3
16 = /dev/cuam0 Callout device for ttyAM0
...
31 = /dev/cuam15 Callout device for ttyAM15
32 = /dev/cudb0 Callout device for ttyDB0
...
39 = /dev/cudb7 Callout device for ttyDB7
40 = /dev/cusg0 Callout device for ttySG0
41 = /dev/ttycusmx0 Callout device for ttySMX0
42 = /dev/ttycusmx1 Callout device for ttySMX1
43 = /dev/ttycusmx2 Callout device for ttySMX2
46 = /dev/cucpm0 Callout device for ttyCPM0
...
49 = /dev/cucpm5 Callout device for ttyCPM5
50 = /dev/cuioc40 Callout device for ttyIOC40
...
81 = /dev/cuioc431 Callout device for ttyIOC431
82 = /dev/cuvr0 Callout device for ttyVR0
83 = /dev/cuvr1 Callout device for ttyVR1
206 char OnStream SC-x0 tape devices
0 = /dev/osst0 First OnStream SCSI tape, mode 0
1 = /dev/osst1 Second OnStream SCSI tape, mode 0
...
32 = /dev/osst0l First OnStream SCSI tape, mode 1
33 = /dev/osst1l Second OnStream SCSI tape, mode 1
...
64 = /dev/osst0m First OnStream SCSI tape, mode 2
65 = /dev/osst1m Second OnStream SCSI tape, mode 2
...
96 = /dev/osst0a First OnStream SCSI tape, mode 3
97 = /dev/osst1a Second OnStream SCSI tape, mode 3
...
128 = /dev/nosst0 No rewind version of /dev/osst0
129 = /dev/nosst1 No rewind version of /dev/osst1
...
160 = /dev/nosst0l No rewind version of /dev/osst0l
161 = /dev/nosst1l No rewind version of /dev/osst1l
...
192 = /dev/nosst0m No rewind version of /dev/osst0m
193 = /dev/nosst1m No rewind version of /dev/osst1m
...
224 = /dev/nosst0a No rewind version of /dev/osst0a
225 = /dev/nosst1a No rewind version of /dev/osst1a
...
The OnStream SC-x0 SCSI tapes do not support the
standard SCSI SASD command set and therefore need
their own driver "osst". Note that the IDE, USB (and
maybe ParPort) versions may be driven via ide-scsi or
usb-storage SCSI emulation and this osst device and
driver as well. The ADR-x0 drives are QIC-157
compliant and don't need osst.
207 char Compaq ProLiant health feature indicate
0 = /dev/cpqhealth/cpqw Redirector interface
1 = /dev/cpqhealth/crom EISA CROM
2 = /dev/cpqhealth/cdt Data Table
3 = /dev/cpqhealth/cevt Event Log
4 = /dev/cpqhealth/casr Automatic Server Recovery
5 = /dev/cpqhealth/cecc ECC Memory
6 = /dev/cpqhealth/cmca Machine Check Architecture
7 = /dev/cpqhealth/ccsm Deprecated CDT
8 = /dev/cpqhealth/cnmi NMI Handling
9 = /dev/cpqhealth/css Sideshow Management
10 = /dev/cpqhealth/cram CMOS interface
11 = /dev/cpqhealth/cpci PCI IRQ interface
208 char User space serial ports
0 = /dev/ttyU0 First user space serial port
1 = /dev/ttyU1 Second user space serial port
...
209 char User space serial ports (alternate devices)
0 = /dev/cuu0 Callout device for ttyU0
1 = /dev/cuu1 Callout device for ttyU1
...
210 char SBE, Inc. sync/async serial card
0 = /dev/sbei/wxcfg0 Configuration device for board 0
1 = /dev/sbei/dld0 Download device for board 0
2 = /dev/sbei/wan00 WAN device, port 0, board 0
3 = /dev/sbei/wan01 WAN device, port 1, board 0
4 = /dev/sbei/wan02 WAN device, port 2, board 0
5 = /dev/sbei/wan03 WAN device, port 3, board 0
6 = /dev/sbei/wanc00 WAN clone device, port 0, board 0
7 = /dev/sbei/wanc01 WAN clone device, port 1, board 0
8 = /dev/sbei/wanc02 WAN clone device, port 2, board 0
9 = /dev/sbei/wanc03 WAN clone device, port 3, board 0
10 = /dev/sbei/wxcfg1 Configuration device for board 1
11 = /dev/sbei/dld1 Download device for board 1
12 = /dev/sbei/wan10 WAN device, port 0, board 1
13 = /dev/sbei/wan11 WAN device, port 1, board 1
14 = /dev/sbei/wan12 WAN device, port 2, board 1
15 = /dev/sbei/wan13 WAN device, port 3, board 1
16 = /dev/sbei/wanc10 WAN clone device, port 0, board 1
17 = /dev/sbei/wanc11 WAN clone device, port 1, board 1
18 = /dev/sbei/wanc12 WAN clone device, port 2, board 1
19 = /dev/sbei/wanc13 WAN clone device, port 3, board 1
...
Yes, each board is really spaced 10 (decimal) apart.
211 char Addinum CPCI1500 digital I/O card
0 = /dev/addinum/cpci1500/0 First CPCI1500 card
1 = /dev/addinum/cpci1500/1 Second CPCI1500 card
...
212 char LinuxTV.org DVB driver subsystem
0 = /dev/dvb/adapter0/video0 first video decoder of first card
1 = /dev/dvb/adapter0/audio0 first audio decoder of first card
2 = /dev/dvb/adapter0/sec0 (obsolete/unused)
3 = /dev/dvb/adapter0/frontend0 first frontend device of first card
4 = /dev/dvb/adapter0/demux0 first demux device of first card
5 = /dev/dvb/adapter0/dvr0 first digital video recoder device of first card
6 = /dev/dvb/adapter0/ca0 first common access port of first card
7 = /dev/dvb/adapter0/net0 first network device of first card
8 = /dev/dvb/adapter0/osd0 first on-screen-display device of first card
9 = /dev/dvb/adapter0/video1 second video decoder of first card
...
64 = /dev/dvb/adapter1/video0 first video decoder of second card
...
128 = /dev/dvb/adapter2/video0 first video decoder of third card
...
196 = /dev/dvb/adapter3/video0 first video decoder of fourth card
216 char Bluetooth RFCOMM TTY devices
0 = /dev/rfcomm0 First Bluetooth RFCOMM TTY device
1 = /dev/rfcomm1 Second Bluetooth RFCOMM TTY device
...
217 char Bluetooth RFCOMM TTY devices (alternate devices)
0 = /dev/curf0 Callout device for rfcomm0
1 = /dev/curf1 Callout device for rfcomm1
...
218 char The Logical Company bus Unibus/Qbus adapters
0 = /dev/logicalco/bci/0 First bus adapter
1 = /dev/logicalco/bci/1 First bus adapter
...
219 char The Logical Company DCI-1300 digital I/O card
0 = /dev/logicalco/dci1300/0 First DCI-1300 card
1 = /dev/logicalco/dci1300/1 Second DCI-1300 card
...
220 char Myricom Myrinet "GM" board
0 = /dev/myricom/gm0 First Myrinet GM board
1 = /dev/myricom/gmp0 First board "root access"
2 = /dev/myricom/gm1 Second Myrinet GM board
3 = /dev/myricom/gmp1 Second board "root access"
...
221 char VME bus
0 = /dev/bus/vme/m0 First master image
1 = /dev/bus/vme/m1 Second master image
2 = /dev/bus/vme/m2 Third master image
3 = /dev/bus/vme/m3 Fourth master image
4 = /dev/bus/vme/s0 First slave image
5 = /dev/bus/vme/s1 Second slave image
6 = /dev/bus/vme/s2 Third slave image
7 = /dev/bus/vme/s3 Fourth slave image
8 = /dev/bus/vme/ctl Control
It is expected that all VME bus drivers will use the
same interface. For interface documentation see
http://www.vmelinux.org/.
224 char A2232 serial card
0 = /dev/ttyY0 First A2232 port
1 = /dev/ttyY1 Second A2232 port
...
225 char A2232 serial card (alternate devices)
0 = /dev/cuy0 Callout device for ttyY0
1 = /dev/cuy1 Callout device for ttyY1
...
226 char Direct Rendering Infrastructure (DRI)
0 = /dev/dri/card0 First graphics card
1 = /dev/dri/card1 Second graphics card
...
227 char IBM 3270 terminal Unix tty access
1 = /dev/3270/tty1 First 3270 terminal
2 = /dev/3270/tty2 Seconds 3270 terminal
...
228 char IBM 3270 terminal block-mode access
0 = /dev/3270/tub Controlling interface
1 = /dev/3270/tub1 First 3270 terminal
2 = /dev/3270/tub2 Second 3270 terminal
...
229 char IBM iSeries/pSeries virtual console
0 = /dev/hvc0 First console port
1 = /dev/hvc1 Second console port
...
230 char IBM iSeries virtual tape
0 = /dev/iseries/vt0 First virtual tape, mode 0
1 = /dev/iseries/vt1 Second virtual tape, mode 0
...
32 = /dev/iseries/vt0l First virtual tape, mode 1
33 = /dev/iseries/vt1l Second virtual tape, mode 1
...
64 = /dev/iseries/vt0m First virtual tape, mode 2
65 = /dev/iseries/vt1m Second virtual tape, mode 2
...
96 = /dev/iseries/vt0a First virtual tape, mode 3
97 = /dev/iseries/vt1a Second virtual tape, mode 3
...
128 = /dev/iseries/nvt0 First virtual tape, mode 0, no rewind
129 = /dev/iseries/nvt1 Second virtual tape, mode 0, no rewind
...
160 = /dev/iseries/nvt0l First virtual tape, mode 1, no rewind
161 = /dev/iseries/nvt1l Second virtual tape, mode 1, no rewind
...
192 = /dev/iseries/nvt0m First virtual tape, mode 2, no rewind
193 = /dev/iseries/nvt1m Second virtual tape, mode 2, no rewind
...
224 = /dev/iseries/nvt0a First virtual tape, mode 3, no rewind
225 = /dev/iseries/nvt1a Second virtual tape, mode 3, no rewind
...
"No rewind" refers to the omission of the default
automatic rewind on device close. The MTREW or MTOFFL
ioctl()'s can be used to rewind the tape regardless of
the device used to access it.
231 char InfiniBand
0 = /dev/infiniband/umad0
1 = /dev/infiniband/umad1
...
63 = /dev/infiniband/umad63 63rd InfiniBandMad device
64 = /dev/infiniband/issm0 First InfiniBand IsSM device
65 = /dev/infiniband/issm1 Second InfiniBand IsSM device
...
127 = /dev/infiniband/issm63 63rd InfiniBand IsSM device
192 = /dev/infiniband/uverbs0 First InfiniBand verbs device
193 = /dev/infiniband/uverbs1 Second InfiniBand verbs device
...
223 = /dev/infiniband/uverbs31 31st InfiniBand verbs device
232 char Biometric Devices
0 = /dev/biometric/sensor0/fingerprint first fingerprint sensor on first device
1 = /dev/biometric/sensor0/iris first iris sensor on first device
2 = /dev/biometric/sensor0/retina first retina sensor on first device
3 = /dev/biometric/sensor0/voiceprint first voiceprint sensor on first device
4 = /dev/biometric/sensor0/facial first facial sensor on first device
5 = /dev/biometric/sensor0/hand first hand sensor on first device
...
10 = /dev/biometric/sensor1/fingerprint first fingerprint sensor on second device
...
20 = /dev/biometric/sensor2/fingerprint first fingerprint sensor on third device
...
233 char PathScale InfiniPath interconnect
0 = /dev/ipath Primary device for programs (any unit)
1 = /dev/ipath0 Access specifically to unit 0
2 = /dev/ipath1 Access specifically to unit 1
...
4 = /dev/ipath3 Access specifically to unit 3
129 = /dev/ipath_sma Device used by Subnet Management Agent
130 = /dev/ipath_diag Device used by diagnostics programs
234-254 char RESERVED FOR DYNAMIC ASSIGNMENT
Character devices that request a dynamic allocation of major number will
take numbers starting from 254 and downward.
240-254 block LOCAL/EXPERIMENTAL USE
Allocated for local/experimental use. For devices not
assigned official numbers, these ranges should be
used in order to avoid conflicting with future assignments.
255 char RESERVED
255 block RESERVED
This major is reserved to assist the expansion to a
larger number space. No device nodes with this major
should ever be created on the filesystem.
(This is probably not true anymore, but I'll leave it
for now /Torben)
---LARGE MAJORS!!!!!---
256 char Equinox SST multi-port serial boards
0 = /dev/ttyEQ0 First serial port on first Equinox SST board
127 = /dev/ttyEQ127 Last serial port on first Equinox SST board
128 = /dev/ttyEQ128 First serial port on second Equinox SST board
...
1027 = /dev/ttyEQ1027 Last serial port on eighth Equinox SST board
256 block Resident Flash Disk Flash Translation Layer
0 = /dev/rfda First RFD FTL layer
16 = /dev/rfdb Second RFD FTL layer
...
240 = /dev/rfdp 16th RFD FTL layer
257 char Phoenix Technologies Cryptographic Services Driver
0 = /dev/ptlsec Crypto Services Driver
257 block SSFDC Flash Translation Layer filesystem
0 = /dev/ssfdca First SSFDC layer
8 = /dev/ssfdcb Second SSFDC layer
16 = /dev/ssfdcc Third SSFDC layer
24 = /dev/ssfdcd 4th SSFDC layer
32 = /dev/ssfdce 5th SSFDC layer
40 = /dev/ssfdcf 6th SSFDC layer
48 = /dev/ssfdcg 7th SSFDC layer
56 = /dev/ssfdch 8th SSFDC layer
258 block ROM/Flash read-only translation layer
0 = /dev/blockrom0 First ROM card's translation layer interface
1 = /dev/blockrom1 Second ROM card's translation layer interface
...
259 block Block Extended Major
Used dynamically to hold additional partition minor
numbers and allow large numbers of partitions per device
259 char FPGA configuration interfaces
0 = /dev/icap0 First Xilinx internal configuration
1 = /dev/icap1 Second Xilinx internal configuration
260 char OSD (Object-based-device) SCSI Device
0 = /dev/osd0 First OSD Device
1 = /dev/osd1 Second OSD Device
...
255 = /dev/osd255 256th OSD Device
384-511 char RESERVED FOR DYNAMIC ASSIGNMENT
Character devices that request a dynamic allocation of major
number will take numbers starting from 511 and downward,
once the 234-254 range is full.
Additional /dev/ directory entries¶
This section details additional entries that should or may exist in the /dev directory. It is preferred that symbolic links use the same form (absolute or relative) as is indicated here. Links are classified as “hard” or “symbolic” depending on the preferred type of link; if possible, the indicated type of link should be used.
Compulsory links¶
These links should exist on all systems:
/dev/fd |
/proc/self/fd |
symbolic |
File descriptors |
/dev/stdin |
fd/0 |
symbolic |
stdin file descriptor |
/dev/stdout |
fd/1 |
symbolic |
stdout file descriptor |
/dev/stderr |
fd/2 |
symbolic |
stderr file descriptor |
/dev/nfsd |
socksys |
symbolic |
Required by iBCS-2 |
/dev/X0R |
null |
symbolic |
Required by iBCS-2 |
Note: /dev/X0R is <letter X>-<digit 0>-<letter R>.
Recommended links¶
It is recommended that these links exist on all systems:
/dev/core |
/proc/kcore |
symbolic |
Backward compatibility |
/dev/ramdisk |
ram0 |
symbolic |
Backward compatibility |
/dev/ftape |
qft0 |
symbolic |
Backward compatibility |
/dev/bttv0 |
video0 |
symbolic |
Backward compatibility |
/dev/radio |
radio0 |
symbolic |
Backward compatibility |
/dev/i2o* |
/dev/i2o/* |
symbolic |
Backward compatibility |
/dev/scd? |
sr? |
hard |
Alternate SCSI CD-ROM name |
Locally defined links¶
The following links may be established locally to conform to the configuration of the system. This is merely a tabulation of existing practice, and does not constitute a recommendation. However, if they exist, they should have the following uses.
/dev/mouse |
mouse port |
symbolic |
Current mouse device |
/dev/tape |
tape device |
symbolic |
Current tape device |
/dev/cdrom |
CD-ROM device |
symbolic |
Current CD-ROM device |
/dev/cdwriter |
CD-writer |
symbolic |
Current CD-writer device |
/dev/scanner |
scanner |
symbolic |
Current scanner device |
/dev/modem |
modem port |
symbolic |
Current dialout device |
/dev/root |
root device |
symbolic |
Current root filesystem |
/dev/swap |
swap device |
symbolic |
Current swap device |
/dev/modem should not be used for a modem which supports dialin as
well as dialout, as it tends to cause lock file problems. If it
exists, /dev/modem should point to the appropriate primary TTY device
(the use of the alternate callout devices is deprecated).
For SCSI devices, /dev/tape and /dev/cdrom should point to the
cooked devices (/dev/st* and /dev/sr*, respectively), whereas
/dev/cdwriter and /dev/scanner should point to the appropriate generic
SCSI devices (/dev/sg*).
/dev/mouse may point to a primary serial TTY device, a hardware mouse
device, or a socket for a mouse driver program (e.g. /dev/gpmdata).
Sockets and pipes¶
Non-transient sockets and named pipes may exist in /dev. Common entries are:
/dev/printer |
socket |
lpd local socket |
/dev/log |
socket |
syslog local socket |
/dev/gpmdata |
socket |
gpm mouse multiplexer |
Mount points¶
The following names are reserved for mounting special filesystems under /dev. These special filesystems provide kernel interfaces that cannot be provided with standard device nodes.
/dev/pts |
devpts |
PTY slave filesystem |
/dev/shm |
tmpfs |
POSIX shared memory maintenance access |
Terminal devices¶
Terminal, or TTY devices are a special class of character devices. A terminal device is any device that could act as a controlling terminal for a session; this includes virtual consoles, serial ports, and pseudoterminals (PTYs).
All terminal devices share a common set of capabilities known as line disciplines; these include the common terminal line discipline as well as SLIP and PPP modes.
All terminal devices are named similarly; this section explains the naming and use of the various types of TTYs. Note that the naming conventions include several historical warts; some of these are Linux-specific, some were inherited from other systems, and some reflect Linux outgrowing a borrowed convention.
A hash mark (#) in a device name is used here to indicate a decimal
number without leading zeroes.
Virtual consoles and the console device¶
Virtual consoles are full-screen terminal displays on the system video
monitor. Virtual consoles are named /dev/tty#, with numbering
starting at /dev/tty1; /dev/tty0 is the current virtual console.
/dev/tty0 is the device that should be used to access the system video
card on those architectures for which the frame buffer devices
(/dev/fb*) are not applicable. Do not use /dev/console
for this purpose.
The console device, /dev/console, is the device to which system
messages should be sent, and on which logins should be permitted in
single-user mode. Starting with Linux 2.1.71, /dev/console is managed
by the kernel; for previous versions it should be a symbolic link to
either /dev/tty0, a specific virtual console such as /dev/tty1, or to
a serial port primary (tty*, not cu*) device, depending on the
configuration of the system.
Serial ports¶
Serial ports are RS-232 serial ports and any device which simulates
one, either in hardware (such as internal modems) or in software (such
as the ISDN driver.) Under Linux, each serial ports has two device
names, the primary or callin device and the alternate or callout one.
Each kind of device is indicated by a different letter. For any
letter X, the names of the devices are /dev/ttyX# and /dev/cux#,
respectively; for historical reasons, /dev/ttyS# and /dev/ttyC#
correspond to /dev/cua# and /dev/cub#. In the future, it should be
expected that multiple letters will be used; all letters will be upper
case for the “tty” device (e.g. /dev/ttyDP#) and lower case for the
“cu” device (e.g. /dev/cudp#).
The names /dev/ttyQ# and /dev/cuq# are reserved for local use.
The alternate devices provide for kernel-based exclusion and somewhat different defaults than the primary devices. Their main purpose is to allow the use of serial ports with programs with no inherent or broken support for serial ports. Their use is deprecated, and they may be removed from a future version of Linux.
Arbitration of serial ports is provided by the use of lock files with
the names /var/lock/LCK..ttyX#. The contents of the lock file should
be the PID of the locking process as an ASCII number.
It is common practice to install links such as /dev/modem which point to serial ports. In order to ensure proper locking in the presence of these links, it is recommended that software chase symlinks and lock all possible names; additionally, it is recommended that a lock file be installed with the corresponding alternate device. In order to avoid deadlocks, it is recommended that the locks are acquired in the following order, and released in the reverse:
The symbolic link name, if any (
/var/lock/LCK..modem)The “tty” name (
/var/lock/LCK..ttyS2)The alternate device name (
/var/lock/LCK..cua2)
In the case of nested symbolic links, the lock files should be installed in the order the symlinks are resolved.
Under no circumstances should an application hold a lock while waiting for another to be released. In addition, applications which attempt to create lock files for the corresponding alternate device names should take into account the possibility of being used on a non-serial port TTY, for which no alternate device would exist.
Pseudoterminals (PTYs)¶
Pseudoterminals, or PTYs, are used to create login sessions or provide
other capabilities requiring a TTY line discipline (including SLIP or
PPP capability) to arbitrary data-generation processes. Each PTY has
a master side, named /dev/pty[p-za-e][0-9a-f], and a slave side, named
/dev/tty[p-za-e][0-9a-f]. The kernel arbitrates the use of PTYs by
allowing each master side to be opened only once.
Once the master side has been opened, the corresponding slave device can be used in the same manner as any TTY device. The master and slave devices are connected by the kernel, generating the equivalent of a bidirectional pipe with TTY capabilities.
Recent versions of the Linux kernels and GNU libc contain support for
the System V/Unix98 naming scheme for PTYs, which assigns a common
device, /dev/ptmx, to all the masters (opening it will automatically
give you a previously unassigned PTY) and a subdirectory, /dev/pts,
for the slaves; the slaves are named with decimal integers (/dev/pts/#
in our notation). This removes the problem of exhausting the
namespace and enables the kernel to automatically create the device
nodes for the slaves on demand using the “devpts” filesystem.