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MKNOD(8)		FreeBSD	System Manager's Manual		      MKNOD(8)

     mknod -- make device special files

     mknod [-m mode] name b|c major minor
     mknod [-m mode] name p

     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 speci-
	     fied, 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 spe-
	     cial files, the type is b.	 All other devices are character type
	     devices, such as terminal and pseudo devices, and are type	c.  A
	     FIFO (also	known as a named pipe) is type p.

     major   The major device number is	an integer number which	tells the ker-
	     nel 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 accept-
	     able to strtoul(3), so that a leading "0x"	indicates a hexadeci-
	     mal number, and a leading "0" will	cause the number to be inter-
	     preted as octal.

     chmod(1), mkfifo(1), mkfifo(2), mknod(2), MAKEDEV(8)

     As	an extension, mknod can	also take multiple lists of parameters in one
     go.  Note that -m is not reset from one list to the next so, for example,

	   mknod -m 700	name b 12 5 name2 b 12 6

     both name and name2 will be mode 700.

     A mknod command appeared in Version 4 AT&T	UNIX.

FreeBSD	13.0			October	6, 2016			  FreeBSD 13.0


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