Documentation/admin-guide/devices.txt

32 		  0 = /dev/ptyp0	First PTY master
33 		  1 = /dev/ptyp1	Second PTY master
35 		255 = /dev/ptyef	256th PTY master
44 		These are the old-style (BSD) PTY devices; Unix98
45 		devices are on major 128 and above and use the PTY
46 		master multiplex (/dev/ptmx) to acquire a PTY on
107 		  0 = /dev/ttyp0	First PTY slave
108 		  1 = /dev/ttyp1	Second PTY slave
110 		255 = /dev/ttyef	256th PTY slave
112 		These are the old-style (BSD) PTY devices; Unix98
144 		number for BSD PTY devices.  As of Linux 2.1.115, this
156 		  2 = /dev/ptmx		PTY master multiplex
1988  128-135 char	Unix98 PTY masters
2084  136-143 char	Unix98 PTY slaves