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

     mknod - build special file

     mknod [-m mode] name [c | b] 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 mode.  mode may be absolute or symbolic, as de-
             scribed in chmod(1).  In symbolic mode strings, the `+' and `-'
             operators are interpreted relative to an assumed initial mode of

     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 hexadec-
             imal number, and a leading ``0'' will cause the number to be in-
             terpreted as octal.

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

     A mknod command appeared in Version 6 AT&T UNIX.

OpenBSD 3.6                     April 18, 1999                               1