Index: book.xml.moresio =================================================================== --- book.xml.moresio +++ book.xml.moresio @@ -6320,12 +6320,11 @@ This example shows two serial ports. The first is on IRQ4, port address - 0x3f8, and has a 16550A-type UART chip. - The second uses the same kind of chip but is on - IRQ3 and is at port address - 0x2f8. Internal modem cards are - treated just like serial ports, except that they - always have a modem attached to the + 0x3f8, and has a 16550 or a 16550-compatible + UART chip. The second uses the same kind of chip but is on + IRQ3 and is at port address 0x2f8. + Internal modem cards are treated just like serial ports, + except that the always have a modem attached to the port. The GENERIC kernel includes @@ -6347,22 +6346,22 @@ The third serial port, sio2, or COM3, - is on /dev/cuad2 for dial-out - devices, and on /dev/ttyd2 for + is on /dev/cuau2 for dial-out + devices, and on /dev/ttyv2 for dial-in devices. What is the difference between these two classes of devices? When - opening /dev/ttydX in blocking mode, + opening /dev/ttyvX in blocking mode, a process will wait for the corresponding - cuadX device to become inactive, and + cuauX device to become inactive, and then wait for the carrier detect line to go active. When - the cuadX device is opened, it makes + the cuauX device is opened, it makes sure the serial port is not already in use by the - ttydX device. If the port is + ttyvX device. If the port is available, it steals it from the - ttydX device. Also, the - cuadX device does not care about + ttyvX device. Also, the + cuauX device does not care about carrier detect. With this scheme and an auto-answer modem, remote users can log in and local users can still dial out with the same modem and the system will take care