You are going about this with blinders on. Unless you are writing baremetal or
kernel code (which most of the languages you listed are not really targeted
toward), you should be asking about writing to serial devices.
You are on Linux and the Linux interfaces for serial ports (which UARTs are)
are pretty much the same on all platforms (be it PC or or the Beagle's). In a
nutshell, they appears as a character device. So what you should be
researching is how to program a serial character device in Linux (or Unix).
Depending the level of control you need, it can range from as simple as
writing to stdout and redirecting to opening up special files and issuing
ioctls.
Once again, if you take off the blinders, the answer to physically
disconnected "uarts" would make more sense. Consider SPP on Bluetooth wireless
which shares the same programming interface as any other serial port.
--
Hunyue Yau
http://www.hy-research.com/