Hello a short update: > I however still observe the buffering effect, i.e. characters sent from the > USBRSA to a serial port is not directly dumped but buffered, and eventually > displayed by cat. Can I set the buffer size somehow or control flushing ? I observe the buffering on the ttySx device only, i.e. cat /dev/ttyS6. From the logfile, I can see that the urbs issued to the USBRSA are queued and sent. If sent data in the other direction, i.e. from ttyS6 to to the USBRSA on ttyUSB0, I do not observe any buffering. cat /dev/ttyUSB0 always dumps the received data directly (unless I sent an echo -n "characters" > /dev/ttyS6, of course). Maybe it is related to the legacy serial device in general, or to the serial card I am using. It is an NetMos Technology PCI 9845 Multi-I/O Controller with 6 serial ports. Cheers Tilman -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
