Hyper-V Program Manager
One interesting feature of Virtual PC / Virtual Server is the ability to map one of the virtual machines COM ports to a text file on the host computer. This can be very handy for logging information on automated tests / batch jobs running inside of virtual machines.
Once you have configured your virtual machine to have its COM port point to a text file - you can write data to the text file from inside of the virtual machine quite easily.
Under DOS / Windows / OS/2 you can use the following commands:
Under Linux the equivalent commands to use are:
Note that under Linux, COM ports are 0 indexed (so ttyS0 = COM1, ttyS1 = COM2). Also note that the Linux /dev/ttyS0 is case sensitive (the S is uppercase).