MAKEDEV(8)
NAME
MAKEDEV - create devices
SYNOPSIS
cd dev; ./MAKEDEV -V
cd dev; ./MAKEDEV [ -n ] [ -v ] update
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
-V Print out version (actually RCS version informa-
tion) and exit.
-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 per-
formed. 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 set-
tings. 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.
DEVICES
General Options
update This only works on kernels which have /proc/inter-
rupts (introduced during 1.1.x). This file is
scanned to see what devices are currently config-
ured 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 is the
standard devices, plus floppy drives, various hard
drives, pseudo-terminals, console devices, basic
serial devices, busmice, and printer ports.
std Standard devices. These are: mem - acess to physi-
cal memory; kmem - access to kernel virtual memory;
null - null device (infinite sink); port - access
to I/O ports; zero - null byte source (infinite
source); core - symlink to /proc/kcore (for kernel
debugging); full - always returns ENOSPACE on
write; ram - ramdisk; tty - to access the control-
ling tty of a process.
local This simply runs MAKEDEV.local. This is a script
that can create any local devices.
Virtual Terminals
console
This creates the devices associated with the con-
sole. This is the virtual terminals ttyx, where x
can be from 0 though 63. The device tty0 is the
currently active vt, and is also known as console.
For each vt, there are two devices vcsx and vcsax,
which are used to generate screen-dumps of the vt
(the vcsx is just the text, and vcsax includes the
attributes).
Serial Devices
ttyS{0..63}
Serial ports and corresponding dialout device. For
device ttySx, there is also the device cuax which
is used to dial out with. This can avoid the need
for cooperative locks in simple situations.
cyclades
Dial-in and dial-out devices for the cyclades
intelligent I/O serial card. The dial in device is
ttyCx and the corresponding dial-out device is cubx
By default devices for 7 lines are created, but
this can be changed to 15 by removing the comment.
Pseudo Terminals
pty[p-s]
Each possible argument will create a bank of 16
master and slave pairs. The current kernel (1.2)
is limited to 64 such pairs. The master pseudo-
terminals are pty[p-s][0-9a-f], and the slaves are
tty[p-s][0-9a-f].
Parallel Ports
lp Standard parallel ports. The devices are created
lp0, lp1, and lp2. 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. Ports are named parx instead of
lpx.
Bus Mice
busmice
The various bus mice devices. This creates the
following devices: logimouse (Logitech bus mouse),
psmouse (PS/2-style mouse), msmouse (Microsoft
Inport bus mouse) and atimouse (ATI XL bus mouse)
and jmouse (J-mouse).
Joystick Devices
js Joystick. Creates js0 and js1.
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
fdxLn. The single letter L identifies the type of
floppy disk (d = 5.25" DD, h = 5.25" HD, D = 3.5"
DD, H = 3.5" HD, E = 3.5" ED). The number n repre-
sents the capacity of that format in K. Thus the
standard formats are fdxd360, fdxh1200, fdxD720,
fdxH1440, and fdxE2880.
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.
hd[a-d]
AT hard disks. The device hdx provides access to
the whole disk, with the partitions being
hdx[0-20]. The four primary partitions are hdx1
through hdx4, with the logical partitions being
numbered from hdx5 though hdx20. (A primary parti-
tion can be made into an extended partition, which
can hold 4 logical partitions). By default, only
the devices for 4 logical partitions are made. The
others can be made by uncommenting them.
Drives hda and hdb are the two on the first con-
troller. If using the new IDE driver (rather than
the old HD driver), then hdc and hdd are the two
drives on the secondary controller. These devices
can also be used to acess IDE CDROMs if using the
new IDE driver.
xd[a-d]
XT hard disks. Partitions are the same as IDE
disks.
sd[a-h]
SCSI hard disks. The partitions are similar to the
IDE disks, but there is a limit of 11 logical par-
titions (sdx5 through sdx15). This is to allow
there to be 8 SCSI disks.
loop Loopback disk devices. These allow you to use a
regular file as a block device. This means that
images of filesystems can be mounted, and used as
normal. This creates 8 devices loop0 through
loop7.
Tape Devices
st[0-7]
SCSI tapes. This creates the rewinding tape device
stx and the non-rewinding tape device nstx.
qic QIC-80 tapes. The devices created are 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
rftx (rewinding) and nrftx (non-rewinding) are cre-
ated. For compatability, devices ftape and nftape
are symlinks to rft0 and nrft0 respectively.
CDROM Devices
scd[0-7]
SCSI CD players.
sonycd Sony CDU-31A CD player.
mcd Mitsumi CD player.
cdu535 Sony CDU-535 CD player.
lmscd LMS/Philips CD player.
sbpcd{,1,2,3}
Sound Blaster CD player. The kernel is capable of
supporting 16 CDROMs, each of which is accessed as
sbpcd[0-9a-f]. These are assigned in groups of 4
to each controller. sbpcd is a symlink to sbpcd0.
Scanner
logiscan
Logitech ScanMan32 & ScanMan 256.
m105scan
Mustek M105 Handscanner.
ac4096 A4Tek Color Handscanner.
Audio
audio This creates the audio devices used by the sound
driver. These include mixer, sequencer, dsp, and
audio.
pcaudio
Devices for the PC Speaker sound driver. These are
pcmixer. pxsp, and pcaudio.
Miscellaneous
sg Generic SCSI devices. The devices created are sg0
through sg7. These allow arbitary commands to be
sent to any SCSI device. This allows for querying
information about the device, or controlling SCSI
devices that are not one of disk, tape or CDROM
(e.g. scanner, 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 BR /dev/stdin , BR /dev/stdout ,
and BR /dev/stderr . (Note, these are just sym-
links into /proc/self/fd).
ibcs2 Devices (and symlinks) needed by the IBCS2 emula-
tion.
apm Devices for power management.
dcf Driver for DCF-77 radio clock.
helloworld
Kernel modules demonstration device. See the mod-
ules source.
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 ker-
nel, look at /proc/net/dev.
SEE ALSO
Linux Allocated Devices, maintained by H. Peter Anvin,
lt;Peter.Anvin@linux.org.
AUTHOR
Nick Holloway, <Nick.Hollowa