On Wed, Jun 28, 2017 at 11:19:09AM +0200, Oliver Neukum wrote: > Am Mittwoch, den 28.06.2017, 08:07 +1000 schrieb Stuart Longland: > > Hi, > > > >> and to select 4-wire ("full duplex") RS-485, one does: > > >> # echo rs485fd > /sys/class/tty/ttyUSB0/standard > > > This looks like something that people will put into udev. > > > So the switch will be done via udev, but the user not necessarily > > > started via udev. Looks like a race to me. > > > > It is a race, but unless a daemon is watching for the very moment that a > > particular serial interface appears, it's one that init scripts are very > > likely to win. > > That is precisely what a demon might do. > > > Short of having a flag that blocks reads/writes until a given sysfs file > > is written to say "I'm ready, go ahead"… there aren't that many options > > I can think of. > > 1) module option No, just no, sorry. -- 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