MAKEDEV(8) Make Linux Devices MAKEDEV(8)
NAME
MAKEDEV - create devices
SYNOPSIS
cd /dev; ./MAKEDEV [ -n ] [ -v ] [ update ]
cd /dev; ./MAKEDEV [ -n ] [ -v ] [ generic ] [ local ] [ group-keyword ... device ... ]
cd /dev; ./MAKEDEV [ -n ] [ -v ] [ -d ] device ...
DESCRIPTION
MAKEDEV is a script that will create the devices in /dev used to interface with drivers in the kernel.
Note that programs giving the error ``ENOENT: No such file or directory'' normally means that the device file is missing, whereas ``ENODEV:
No such device'' normally means the kernel does not have the driver configured or loaded.
OPTIONS
-n Do not actually update the devices, just print the actions that would be performed.
-d Delete the devices. The main use for this flag is by MAKEDEV itself.
-v Be verbose. Print out the actions as they are performed. This is the same output as produced by -n.
CUSTOMISATION
Since there is currently no standardisation in what names are used for system users and groups, it is possible that you may need to modify
MAKEDEV to reflect your site's settings. Near the top of the file is a mapping from device type to user, group and permissions (e.g. all
CD-ROM devices are set from the $cdrom variable). If you wish to change the defaults, this is the section to edit.
GENERAL OPTIONS
update This only works on kernels which have /proc/interrupts (introduced during 1.1.x). This file is scanned to see what devices are cur-
rently configured into the kernel, and this is compared with the previous settings stored in the file called DEVICES. Devices which
are new since then or have a different major number are created, and those which are no longer configured are deleted.
generic
Create a generic subset of devices. This subset consists of the standard devices, plus floppy drives, various hard drives, CD-ROM
drives, pseudo-terminals, console devices, basic serial devices, busmice, audio devices, video framebuffers, printer ports, and some
specialized devices. The generic subset varies somewhat according to architecture; see the /dev/MAKEDEV script itself for details.
local This simply runs MAKEDEV.local. This is a script that can create any local devices.
DEVICE GROUPS
MAKEDEV creates groups of devices when passed keywords for the group. Each listing below shows the MAKEDEV keyword and then lists the
devices which will be created. Many devices can also be specified individually.
STANDARD DEVICES
std Creates this group of standard devices: mem for access to physical memory, kmem for access to kernel virtual memory, null the null
device (infinite sink), port for access to I/O ports, zero the null byte source (infinite source), core, a symlink to /proc/kcore
(for kernel debugging), full which always returns ENOSPACE on write, random and urandom random byte generators, and tty to access
the controlling tty of a process. The loopback disk devices loop0 through loop7 are also created in the std group. These allow you
to use a regular file as a block device. A filesystem image can be mounted, and used as though it were a filesystem on a partition
or other block device. loop may also be used as a separate keyword to create the 8 loop devices. Finally, the ram group of memory
devices is also created by the std keyword (see below).
MEMORY DEVICES
ram This is the keyword used to generate the ramdisk devices ram{0..16} and the ram symlink. This group does not include initrd.
initrd Ramdisk which has been pre-initialized by a bootloader. initrd is not created in the ram group; it must be specifically included in
the command line if you want it to be created.
cpu or microcode
Creates the CPU microcode update interface in the cpu/ folder, with devices microcode, and subfolders {0..3} each containing devices
msr and cpuid.
rom Creates the rom{0..7} rrom{0..7} flaxh{0..7} and rflash{0..7} flash memory card devices. rrom and rflash devices are read-only.
CONSOLE DEVICES
console
This keyword creates virtual consoles; tty{0..63} devices, the corresponding vcs and vcsa devices which are used to generate screen-
dumps, and the console device itself plus appropriate symlinks. To create the console device alone, use consoleonly. The device
tty0 is the currently active virtual console. The console device serves the same function.
PSEUDO TERMINALS
pty This keyword creates the Pseudo-TTY masters pty{a..e,p..z} and corresponding tty{a..e,p..z} devices, along with ptmx. Each possible
argument will create a bank of 16 master and slave pairs. The master pseudo-terminals are pty{p..s}{0..9a..f}, and the slaves are
tty{p..s}{0..9a..f}.
SERIAL DEVICES
ttyS{0..63}
Standard serial ports. There is no group keyword, you must specify these individually. However ttyS{0..3} are created under the
generic option for most architectures.
cyclades or ttyC
Creates Cyclades ports ttyC{0..31}.
digi or ttyD
Creates Digiboard serial card ports ttyD{0..15}.
stallion or ttyE
Creates Stallion devices ttyE{0..255} and staliomem{0..3}.
computone or ttyF
Creates CompuTone serial card ports ttyH{0..255} and special devices ip2ipl{0,4,8,12} and ip2stat{1,5,9,13}.
chase or ttyH
Creates Chase serial card ports ttyH{0..15}.
isdnmodem or ttyI
Creates isdn4linux virtual modem ports ttyI{0..63}.
isdn-tty
Also creates isdn4linux virtual modem ports ttyI{0..7}.
isdnbri
Creates ISDN BRI driver devices isdn{0..63} isdnctrl{0..63} ippp{0..63} and isdninfo.
isdn-io
Also creates ISDN BRI driver devices isdn{0..7} isdnctrl{0..7} ippp{0..7} and isdninfo. The isdn-ippp keyword can be used sepa-
rately to create only the ippp{0..7} devices.
ppp Creates a device independent PPP interface.
dcbri Creates Spellcaster DataComm/BRI ISDN card devices dcbri{0..3}.
riscom or ttyL
Creates Riscom serial card ports ttyL{0..15}.
PAM or ttyM
Creates PAM multimodem (or ISI serial card) ports ttyM{0..15}.
ESP or ttyP
Creates ESP ports ttyP{0..4}.
rocketport or ttyR
Creates Rocketport devices ttyR{0..63}.
ttyV Creates Comtrol VS-1000 serial controller ports ttyV{0..15}.
specialixIO8 or ttyW
Creates Specialix IO8+ ports ttyW{0..15}.
specialix or ttyX
Creates Specialix ports ttyX{0..15}.
i2c Creates i2c{0..7} devices for the I2C bus interface.
tlk Philips SAA5249 Teletext signal decoder {2.6} ports tlk{0..3}.
PARALLEL PORTS
lp Creates the standard parallel ports lp0, lp1, and lp2 normally used for printers. These correspond to ports at 0x3bc, 0x378 and
0x278. Hence, on some machines, the first printer port may actually be lp1.
par Alternative to lp. The same ports are created, but are named par{0..2} instead of lp{0..2}.
parport
Creates raw parallel ports parport0, parport1, and parport2.
slm Creates the Atari SLM ACSI laser printer (68k/Atari) ports slm{0..3}.
pg Parallel port generic ATAPI interface (devices pg{0..3}.
paride Parallel port IDE disk devices pd{a..d} with 15 partitions on each. Also creates pcd{0..3} and pf{0..3}.
OTHER BUS PORTS
netlink or tap
Creates NetLink devices route skip fwmonitor and tap{0..15} Ethertap devices. The tapx virtual ethernet device was designed as low
level kernel support for Ethernet tunneling. Userland application can write Ethernet frame to /dev/tapX and the kernel will receive
this frame from tapX interface. Every frame the kernel writes to a tapX interface can be read by a userland application from the
corresponding /dev/tapX device.
enskip ENskip kernel encryption package.
qng ComScire Quantum Noise Generator.
ipsec The Free S/WAN implementation of IPSEC.
adb On powerpc, creates adb for the Apple Data Bus and adbmouse. On m68k, adb creates the ACSI disk device adb and partitions adb1
through adb15.
hamradio
Creates the scc{0..7} and bc{0..3} device groups.
comx Creates COMX devices comx{0..4}.
irda Creates IrCOMM devices (IrDA serial/parallel emulation) ircomm0 ircomm1 irlpt0 and irlpt1.
comedi Control and Measurement devices comedi{0..3}.
MOUSE DEVICES
busmice
This keyword creates the following devices: logibm (Logitech bus mouse), psaux (PS/2-style mouse), inportbm (Microsoft Inport bus
mouse) and atibm (ATI XL bus mouse) and jbm (J-mouse).
m68k-mice
Creates mouse devices for the m68k architecture, including: amigamouse, amigamouse1, atarimouse and adbmouse.
input On powerpc, this keyword creates the input folder which groups input devices mice, mouse{0..3}, event{0..3}, and js{0..3} (joy-
stick), and creates these devices inside.
JOYSTICK DEVICES
js Joystick. Creates js0 and js1.
djs Digital joystick. Creates djs0 and djs1.
USB DEVICES
usb USB is a general purpose I/O bus which can serve many purposes. The usb keyword creates a usb folder, and devices in the folder:
lp{0..15} (printer), mouse{0..15} (USB connected mice), ez{0..15} (firmware loaders) scanner{0..15} (scanner interfaces), tty-
ACM{0..15} and ttyUSB{0..15} (dialout devices), and rio500 the Diamond Rio 500 device.
DISK DEVICES
fd{0..7}
Floppy disk devices. The device fdx is the device which autodetects the format, and the additional devices are fixed format (whose
size is indicated in the name). The other devices are named as fdx{dqhu}n. The single letter (d, q, hor 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 number n represents the
capacity of that format in K. Thus the standard formats are fdxd360, fdxh1200, fdx720, fdx1440, and fdx2880.
For more information see Alain Knaff's fdutils package.
Devices fd0* through fd3* are floppy disks on the first controller, and devices fd4* through fd7* are floppy disks on the second
controller.
fd{0..7}-bare
Creates just the autodetecting floppy device specified, without the fixed format devices.
hd{a..l}
AT (ide) hard disks. The device hdx provides access to the whole disk, with the partitions being hdx{1..63}. For i386, the four
primary partitions are hdx1 through hdx4, with the logical partitions being numbered from hdx5 though hdx20. (A primary partition
can be made into an extended partition, which can hold 4 logical partitions). Other architectures may not differentiate partition
types. By default, devices for 20 logical partitions are made. The kernel supports up to 63 partitions per device.
Drives hda and hdb are the two on the primary controller hdc and hdd are the two drives on the secondary controller. These devices
can also be used to access IDE CDROMs. Additional devices hd{e..l} can be created.
xd{a..d}
XT hard disks. Partitions are the same as IDE disks, except only 8 partitions are created.
sd{a..h}
SCSI hard disks. The partitions are similar to the IDE disks, but there is a limit of 11 logical partitions sdx5 through sdx15, to
allow there to be 8 SCSI disks on a system (addresses 0 through 7).
sd{i..z}
and sd{a..d}{a..z} The kernel (and MAKEDEV) can handle up to 128 SCSI disks (up to sddx). 15 partition devices are created for
each.
eda edb
MCA ESDI hard disk. Partitions are handled the same as hd.
dasd{a..z}
Direct Access Storage Devices for the s390 architecture. Currently only one device partition is created (for example, dasda1).
ada{a..p}
ACSI disk (68k/Atari). 15 partitions are created for each.
dac960.{0..7}
Mylex DAC960 PCI RAID controller. For this device, an rd directory is created. 32 logical devices cxd{0..31} are created for each
unit x specified, each with 7 partitions cxd{0..31}p{1..7}. The dac960 keyword will create all 7 units at once.
dpti Adaptec I2O RAID and DPT SmartRAID V I2O controllers. Creates 7 devices for handling up to 7 controllers.
ataraid.{0..7}
Obsolete, device not in current devices.txt. For this device, an ataraid directory is created. dx is created for each unit x speci-
fied, and 15 partitions dxp{1..15}. The ataraid keyword will create all 7 units at once.
i2o.hd{a..d}{a..z}
I2O based harddisk drives. Device nodes are located in the i2o directory. The filename is followed by a number that specifies the
partition on each disk. The numbers are handled the same as hd.
ida.{0..7}
Compaq Intelligent Drive Array. For this device, an ida directory is created. 16 logical devices cxd{0..15} are created for each
unit x specified, each with 15 partitions cxd{0..15}p{1..15}. The ida keyword will create the first three units.
cciss.{0..7}
Compaq Next Generation Drive Array. For this device, a cciss directory is created. 16 logical devices cxd{0..15} are created for
each unit x specified, each with 15 partitions cxd{0..15}p{1..15}. The cciss keyword will create the first three units.
md Creates Metadisk (RAID) disk array with 16 devices.
TAPE DEVICES
st{0..7}
SCSI tape devices. This creates the rewinding tape device stx and the non-rewinding tape device nstx, for each of modes 0 through
3.
qic QIC-11, -24, -120, and -150 tapes. The devices created are ntpqic11 tpqic11 ntpqic24 tpqic24 ntpqic120 tpqic120 ntpqic150 and
tpqic150 tape devices, along with rmt8, rmt16, tape-d, and tape-reset.
ftape
Floppy driver tapes (QIC-117). There are 4 methods of access depending on the floppy tape drive. For each of access methods 0, 1,
2 and 3, the devices qftx zqftx and rawqftx (rewinding) and nqftx nzqftx nrawqdtx (non-rewinding) are created. For compatibility,
devices ftape and nftape are symlinks to qft0 and nqft0 respectively.
ht0 Creates IDE tape devices ht0 and nht0.
pt{0..3}
Creates parallel port ATAPI tape devices pt{0..3} and npt{0..3}.
CDROM DEVICES
sr or scd or scd-all
Creates scd{0..16} SCSI CD players and sr{0..16} symlinks for these devices. cdrom is a symlink which can be created by the user to
the active CD device. It is not created by MAKEDEV.
pktcdvd
Provides packet writing devices pktcdvd{0..3} for CD/DVD.
pcd{0..3}
Parallel port ATAPI CD-ROM devices
sonycd Sony CDU-31a CD-ROM
mcd Mitsumi CD-ROM
mcdx Obsolete, device not in current devices.txt.
cdu535 Sony CDU-535 CD-ROM
lmscd Philips LMS CM-205 CD-ROM. The newer name for this device is cm205, but MAKEDEV creates only lmscd at this time.
cm206cd
Philips LMS CM-206 CD-ROM
bpcd MicroSolutions BackPack parallel port CD-ROM (Obsolete - use pcd)
sbpcd{0..15}
Matsushita (Panasonic/SoundBlaster) CD-ROM. Units {0..3} are created with the keyword sbpcd.
aztcd Aztech/Orchid/Okano/Wearnes CD-ROM
gscd GoldStar CD-ROM
optcd Optics Storage CD-ROM
sjcd Sanyo CD-ROM
hitcd Hitachi CD-ROM
SCANNERS
logiscan
Logitech ScanMan32 & ScanMan 256.
m105scan
Mustek M105 Handscanner.
ac4096 A4Tek Color Handscanner.
AUDIO DEVICES
audio This creates the audio devices used by the sound driver. These include mixer mixer{1..3} (Mixer controls), sequencer (Audio
sequencer), dsp dsp{1..3} (Digital audio), sndstat (Sound card status information), audioctl (SPARC audio control device) and audio
audio{1..3} (Sun-compatible digital audio). MIDI devices are midi00 through midi03, midi{0..3}, rmidi{0..3}, smpte{0..3}. In addi-
tion, devices mpu401data and mpu401stat are created.
pcaudio
Devices for the PC Speaker sound driver. These are pcmixer, pxsp, and pcaudio.
VIDEO DEVICES
fb Creates framebuffer devices fb{0..7}, fb{0..7}current, fb{0..7}autodetect.
fb{0..7}
If the framebuffer number x is specifed, a group of fbxuser{0..7} devices is created.
3dfx is the 3Dfx Voodoo Graphics device.
agpgart
AGP Graphics Address Remapping Table
video video4linux v4l radio
Each of these keywords produces the same result: Video capture/overlay devices video{0..63}, Radio devices radio{0..63}, Teletext
devices vtx{0..31}, and Vertical blank interrupt devices vbi{0..31}. In addition, the winradio0 and winradio1 devices, and vtx and
vttuner devices, and symlinks radio video and vbi are created.
srnd miroMEDIA Surround board devices srnd0 and srnd1.
fgrab Matrox Meteor frame grabber {2.6}. Creates mmetfgrab, wvisfgrab, iscc0, iscc1, isccctl0, isccctl1, dcxx0, and dcxx1.
MISCELLANEOUS DEVICES
sg or sg-all
Generic SCSI devices. The devices created are sg0 through sg16. These allow arbitary commands to be sent to any SCSI device, to
query information or control SCSI devices that are not disk, tape or CDROM (for example, scanner or writeable CDROM).
fd To allow an arbitary program to be fed input from file descriptor x, use /dev/fd/x as the file name. This also creates /dev/stdin,
/dev/stdout, and /dev/stderr. (Note, these are just symlinks into /proc/self/fd).
ibcs2 Devices socksys spx (and symlinks nfsd XOR) needed by the IBCS2 emulation.
apm apm_bios Advanced Power Management BIOS device.
dcf Driver for DCF-77 radio clock.
helloworld
Kernel modules demonstration device. See the modules source.
xfs or arla
Arla XFS network file system.
capi CAPI 2.0 interface ports capi20{01..20}.
ubd User-mode block devices ubd{0..255}.
nb{0..7}
Network block devices.
raw Creates the raw block device interface raw device, the rawctl symlink, and raw{1..8}.
raw1394
IEEE 1394 (Firewire).
misc This keyword creates all the following devices. You may find the device explanations in other categories in this man page, many
under OTHER DEVICES below. logibm, psaux, inportbm, atibm, jbm, amigamouse, atarimouse, sunmouse, amigamouse1, smouse, pc110pad,
adbmouse, beep, modreq, watchdog, temperature, hwtrap, exttrp, apm_bios, rtc, openprom, relay8, relay16, msr, pciconf, nvram, hfmo-
dem, led, mergemem, pmu.
Network Devices
Linux used to have devices in /dev for controlling network devices, but that is no longer the case. To see what network devices are
known by the kernel, look at /proc/net/dev.
OTHER DEVICES
Many of these devices are architecture-specific.
scc Z8530 HDLC driver (HAM radio)
bc Baycom radio modem (HAM radio)
cfs0 or cfs or coda
Coda network file system
sunmouse
Sun mouse
smouse Simple serial mouse driver
pc110pad
IBM PC-110 digitizer pad
vrtpanel
Vr41xx embedded touch panel
vpcmouse
Connectix Virtual PC Mouse
beep Fancy beep device
modreq Kernel module load request {2.6}
watchdog
Watchdog timer port
temperature
Machine internal temperature
hwtrap Hardware fault trap
exttrp External device trap
rtc Real Time Clock
efirtc Real Time Clock
openprom
SPARC OpenBoot PROM
relay8 Berkshire Products Octal relay card
relay16
Berkshire Products ISO-16 relay card
msr x86 model-specific registers {2.6}
pciconf
PCI configuration space
nvram Non-volatile configuration RAM
hfmodem
Soundcard shortwave modem control {2.6}
graphics
Linux/SGI graphics device
opengl Linux/SGI OpenGL pipe
gfx Linux/SGI graphics effects device
lcd Front panel LCD display
led Front panel LEDs
mergemem
Memory merge device
pmu Macintosh PowerBook power manager
isictl MultiTech ISICom serial control
ac Applicom Intl Profibus card
nwbutton
Netwinder external button
nwdebug
Netwinder debug interface
nwflash
Netwinder flash memory
userdma
User-space DMA access
smbus System Management Bus
lik Logitech Internet Keyboard
ipmo Intel Intelligent Platform Management
vmmon VMWare virtual machine monitor
tcldrv Technology Concepts serial control
specialix_sxctl
Specialix serial control
specialix_rioctl
Specialix RIO serial control
smapi or thinkpad
IBM Thinkpad smapi device, and a symlink thinkpad.
srripc QNX4 API IPC manager
usemaclone
Semaphore clone device
ipmi or ipmikcs
Intelligent Platform Management
uctrl SPARCbook 3 microcontroller
gtrsc Gorgy Timing radio clock
cbm Serial CBM bus
jsflash
JavaStation OS flash SIMM
xsvc High-speed shared-mem/semaphore service
vrbuttons
Vr41xx button input device
toshiba
Toshiba laptop SMM support
perfctr
Performance-monitoring counters
intel_rng
Intel i8x0 random number generator
atomicps
Atomic shapshot of process state data
irnet IrNET device
smbusbios
SMBus BIOS
ussp_ctl
User space serial port control
crash Mission Critical Linux crash dump facility
nas_xbus
NAS xbus LCD/buttons access
d7s SPARC 7-segment display
zkshim Zero-Knowledge network shim control
sexec Signed executable interface
kchuid Inter-process chuid control
mptctl Message passing technology (MPT) control
button/gulpb
Transmeta GULP-B buttons
compaq/cpqphpc
Compaq PCI Hot Plug Controller
compaq/cpqrid
Compaq Remote InsightDriver
elographics/e2201
Elographics touchscreen E271-2201
fujitsu/apanel
Fujitsu/Siemens application panel
i2o/ctl
I2O configuration manager
impi/bt
IMPI coprocessor block transfer
impi/smic
IMPI coprocessor stream interface
input/mouse
Linux/SGI Irix emulation mouse
input/keyboard
Linux/SGI Irix emulation keyboard
modems/mwave
MWave modem firmware upload
mvista/hssdsi
Montavista PICMG hot swap system driver
mvista/hasi
Montavista PICMG high availability
net/tun
TAP/TUN network device
ni/natmotn
National Instruments Motion
scanners/cuecat
:CueCat barcode scanner
touchscreen/ucb1x00
UCB 1x00 touchscreen
touchscreen/mk712
MK712 touchscreen
video/em8300
EM8300 DVD decoder control
video/em8300_mv
EM8300 DVD decoder video
video/em8300_ma
EM8300 DVD decoder audio
video/em8300_sp
EM8300 DVD decoder subpicture
watchdogs/{0..3}
Watchdog devices 0 through 3
SEE ALSO
Linux Allocated Devices, maintained by H. Peter Anvin, <Peter.Anvin@linux.org>, and devices.txt in the Linux kernel source.
AUTHOR
Nick Holloway, rewritten and updated by Chris Tillman
Linux May 17 2002 MAKEDEV(8)