Non blocking mode undesiderable behavior

[paocalvi]

Tested in WINDOWS 7 64 bit.
The non-blocking mode behaves in a weird way. If you set the ReadTimeout to 5 seconds, it waits IN ANY CASE, input arriving or not 5 seconds before giving the data out. This is due to
timeouts.ReadIntervalTimeout = 0
timeouts.ReadTotalTimeoutMultiplier = 0
timeouts.ReadTotalTimeoutConstant = uint32(timeoutMs)
While these may be the desired behavior, probably what people wants when setting a timeout is having the data immediately unless the timeout passes without ANY data. This can be achieved with:
timeouts.ReadIntervalTimeout = MAXDWORD
timeouts.ReadTotalTimeoutMultiplier = MAXDWORD
timeouts.ReadTotalTimeoutConstant = uint32(timeoutMs)
I suggest to modify the code or to add a flag to decide which is the wanted behavior.
Thanks for the great job.

Paolo