Ruben J=F6nsson ha scritto:
> For example: The PC software is talking to a virtual serial port that is =

> connected to a USB device. When the PC software has opened the port it ne=
ver =

> expects the port to go away, which is reasonable considering that a stand=
ard =

> serial port can't be unplugged. However, when the USB device is unplugged =

> (perhaps by accident) really weird things can happen with the PC software=
. I =

> have not been able to reliably catch any exceptions caused by this and mo=
st of =

> the time the PC software just hangs. Sometimes I even have had to restart=
 the =

> computer (XP) before I can get the communication up and running again.


In theory, a WM_DEVICECHANGE message (in Windows) should alert you of =

what is going on. I say in theory since I'm more or less aware of the =

subtle details in that :)

I used mostly HID Generic devices: in them, the Handles usually become =

no longer valid, both Reads and Writes usually Fails, and so do =

semaphores and Waits... so you can more or less recover.



-- =


Ciao, Dario
--
Cyberdyne
-- =

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