[Bug 9356] Serial communication not working since wine-0.9.33

http://bugs.winehq.org/show_bug.cgi?id=9356

--- Comment #14 from Lei Zhang   2007-11-24 22:05:35 ---
well, I ended up not looking at this bug because I didn't have a computer with
a serial port...

now that I do, I tried out Hactronic and here's what I found:

In NtReadFile(), with the old code, we would try to do a read(), which returns
0, and NtReadFile() returns. NtReadFile() gets called repeatedly until I hit
cancel, or presumably until when it actually reads some data.

With the new code, read() returns EAGAIN, so we keep going until we call poll()
later in NtReadFile() with an infinite timeout. Since there's no hardware
connected to the serial port, the poll() call hangs.