mknod: Add support for making FIFOs

mknod.1

@@ -8,25 +8,32 @@
 .Nm
 .Op Fl m Ar mode
 .Ar name
-.Ar type
+.Cm b Ns | Ns Cm c Ns | Ns Cm u
 .Ar major
 .Ar minor
+.Nm
+.Op Fl m Ar mode
+.Ar name
+.Cm p
 .Sh DESCRIPTION
 .Nm
-creates a special device file named
-.Ar name
-with major number
+creates a special file named
+.Ar name .
+.Pp
+The following special file types are supported:
+.Bl -tag -width Ds
+.It Cm b
+A block device.
+.It Cm c | u
+A character device.
+.It Cm p
+A named pipe.
+.El
+.Pp
+Block and character devices are created with major number
 .Ar major ,
 and minor number
 .Ar minor .
-.Ar type
-specifies what kind of special file will be created and must be one of:
-.Bl -tag -width Ds
-.It Ar u | c
-A character device.
-.It Ar b
-A block device.
-.El
 .Sh OPTIONS
 .Bl -tag -width Ds
 .It Fl m