Hi, it occurs to me that usb serial drivers (at least mct_u232 that I use for my u232-p9) don't drain output on close. here's the summary of the behaviour I observe:
open() write(16 bytes or less) close() // nothing gets sent open() write(17 bytes or more) close() // everything gets sent open() write(however many bytes) tcdrain() close() // everything gets sent open() write(however many bytes) sleep(enough time) close() // everything gets sent for comparison, all these cases yield full transmission on PC serial port. serial port settings are 9600 8N1, though I don't think it matters much, apart from baudrate perhaps. The observation is made on 2.4.22. I compared 2.4.22 that I'm running now with 2.6.0-test10, and there don't seem to be any differences in code which would suggest the issue is already solved. Quick grep on tty_wait_until_sent yielded only acceleport and whiteheat. Unless there's some unspoken rule that usb converters don't have to drain, someone should prolly go through all the drivers and fix some? Actually this in itself doesn't bother me too much - so what you can't echo "hello" > /dev/usb/tts/0; my real trouble is with n_r3964 which looses characters on mct_u232 and works alright on pc serial port, though I think that is something I have to fix myself ;-) ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
