ultrix man page for mknod

mknod(8)						      System Manager's Manual							  mknod(8)

Name
       mknod - make special file

Syntax
       /etc/mknod name [ c ] [ b ] major minor
       /etc/mknod name p

Description
       The  command makes a special file.  The first argument is the name of the entry.  The second is b if the special file is block-type (disks,
       tape) or c if it is character-type (other devices).  The last two arguments are numbers specifying the major  device  type  and	the  minor
       device (for example, unit, drive, or line number).

       The assignment of major device numbers is specific to each system.  These numbers are obtained from the system source file conf.c.

       The command can also be used to create fifo's, also known as named pipes, (second case in the Syntax section above).

See Also
       mknod(2)

																	  mknod(8)