mknod - Creates a special file
/usr/sbin/mknod special_file [b major_device#
minor_device# | c major_device# minor_device#]
/usr/sbin/mknod filename p
Indicates that the special file corresponds to a blockoriented
device (disk or tape) Indicates that the special
file corresponds to a character-oriented device Creates
named pipes (FIFOs)
The mknod command makes a directory entry. The first argument
is the name of the special device file. Select a
name that is descriptive of the device.
The mknod command has two forms. In the first form, the
second argument is the b or c flag. The last two arguments
are numbers specifying the major_device, which helps
the operating system find the device driver code, and the
minor_device, the unit drive, or line number, which may be
either decimal or octal.
The assignment of major device numbers is specific to each
system. You can determine the device numbers by examining
the conf.c system source file. If you change the contents
of the conf.c file to add a device driver, you must
rebuild the kernel.
In the second form of mknod, you use the p flag to create
named pipes (FIFOs).
A user who is root can create a character or block special
To create the special file for a new drive,
/dev/disk/dsk20, with a major device number of 1 and a
minor device number of 2, enter: mknod /dev/disk/dsk20 b
This command creates the special file,
/dev/disk/dsk20, which is a block special file with
major device number 1 and minor device number 2.
To create a pipe named fifo, enter: mknod fifo p
This command creates the pipe fifo, which is not
necessarily in the current directory.
Specifies the command path Specifies the system device
numbers specification file
[ Back ]