NAME
mknod
—
make device special files
SYNOPSIS
mknod |
[-m mode]
name
b |c major
minor |
mknod |
[-m mode]
name p |
DESCRIPTION
The mknod
command creates device special
files. Normally the shell script /dev/MAKEDEV is
used to create special files for commonly known devices; it executes
mknod
with the appropriate arguments and can make
all the files required for the device.
The options are as follows:
-m
mode- Set the file permission bits of newly created device special files to
mode. The mode argument can be in any of the formats
specified to the
chmod(1) utility. If a symbolic mode is specified, the operators
‘
+
’ and ‘-
’ are interpreted relative to an initial mode of “a=rw”.
To make nodes manually, the arguments are:
- name
- Device or FIFO name. For example “sd” for a SCSI disk or a “pty” for pseudo-devices. FIFOs may be named arbitrarily by the user.
b
|c
|p
- Type of device or FIFO. If the device is a block type device such as a
tape or disk drive which needs both cooked and raw special files, the type
is
b
. All other devices are character type devices, such as terminal and pseudo devices, and are typec
. A FIFO (also known as a named pipe) is typep
. - major
- The major device number is an integer number which tells the kernel which device driver entry point to use. To learn what major device number to use for a particular device, check the file /dev/MAKEDEV to see if the device is known.
- minor
- The minor device number tells the kernel which subunit the node
corresponds to on the device; for example, a subunit may be a filesystem
partition or a tty line.
Major and minor device numbers can be given in any format acceptable to strtoul(3), so that a leading “0x” indicates a hexadecimal number, and a leading “0” will cause the number to be interpreted as octal.
SEE ALSO
chmod(1), ksh(1), mkfifo(1), mkfifo(2), mknod(2), MAKEDEV(8)
STANDARDS
mknod
also exists as a built-in to
ksh(1).
HISTORY
A mknod
command appeared in
Version 6 AT&T UNIX.