В чем разница между `/ dev / ttyS0` и` / dev / ttys0`?
В Linux в чем разница между /dev/ttyS0 и /dev/ttys0?
Я знаю, что первый - это последовательный порт, но как насчет второго, маленького s?
Ответы 3
For a pseudo terminal pair such as ptyp3 and ttyp3, the pty... is the master or controlling terminal and the tty... is the slave. There are only 16 ttyp's: ttyp0-ttypf (f is a hexadecimal digit). To get more pairs, the 3 letters q, r, s may be used instead of p. For example the pair ttys8, ptys8 is a pseudo terminal pair. The master and slave are really the same "port" but the slave is used by the application program and the master is used by a network program (or the like) which supplies (and gets) data to/from the slave port.
В файле Linux devices.txt в документации ядра говорится:
3 char Pseudo-TTY slaves
0 = /dev/ttyp0 First PTY slave
1 = /dev/ttyp1 Second PTY slave
...
255 = /dev/ttyef 256th PTY slave
These are the old-style (BSD) PTY devices; Unix98
devices are on major 136 and above.
и продолжает говорить
4 char TTY devices
0 = /dev/tty0 Current virtual console
1 = /dev/tty1 First virtual console
...
63 = /dev/tty63 63rd virtual console
64 = /dev/ttyS0 First UART serial port
...
255 = /dev/ttyS191 192nd UART serial port
UART serial ports refer to 8250/16450/16550 series devices.
Older versions of the Linux kernel used this major
number for BSD PTY devices. As of Linux 2.1.115, this
is no longer supported. Use major numbers 2 and 3.
Я не знаю, насколько это вам поможет, но должно помочь вам начать в правильном направлении.