man > ttyS(4)

ttyS(4)                               Kernel Interfaces Manual                               ttyS(4)

NAME
       ttyS - serial terminal lines

DESCRIPTION
       ttyS[0-3] are character devices for the serial terminal lines.

       They are typically created by:

           mknod -m 660 /dev/ttyS0 c 4 64 # base address 0x3f8
           mknod -m 660 /dev/ttyS1 c 4 65 # base address 0x2f8
           mknod -m 660 /dev/ttyS2 c 4 66 # base address 0x3e8
           mknod -m 660 /dev/ttyS3 c 4 67 # base address 0x2e8
           chown root:tty /dev/ttyS[0-3]

FILES
       /dev/ttyS[0-3]

SEE ALSO
       chown(1), mknod(1), tty(4), agetty(8), mingetty(8), setserial(8)

Linux man-pages 6.7                          2023-10-31                                      ttyS(4)