* On Mon, 23 Mar 2009, Chris Teague wrote:
very useful tool would be a serial port loopback device. Rather than require conformance testers to attach a hardware loopback device (NULL modem) to a physical port, could we create some virtual ports in wine and connect them together? Maybe com98 and com99 for example? Anything written to one of the ports would be sent to the other one.
Chris, none of my very business, but do you need to test only Tx/Rx lines, o some more? (like DTR, RTS and the rest)
* On Tue, 24 Mar 2009, Alexandre Julliard wrote:
Serial data and ioctls are forwarded straight to the kernel, so you'd need to put the loopback driver in the kernel, not in Wine.
Basic tests could probably cover Tx/Rx signals only, so IMHO none kernel module would be necessary -- some user space app can suffice (remserial, socat, nullmodem). But that would tie such test to a specific configuration of a particular linux box...
Alexandre, for the core operation your proposal sounds very reasonable, but in the case of winetest, how it would work on Windows?
For tests, I suppose Wine really needs some stubby serial driver (eg one comming from the mentioned com0com), which would then communicate with ntdll/wineserver, where the missing functionality could probably be redirected to the linux kernel, when it's implemented there. No?
With regard to Chris: personally I would start hacking at making com0com to work on Wine.