ZMODEM file transfer between Windows VM on VirtualBox and Linux

This is to show an alternative to transfer a file between host (Linux) and Windows XP running over VirtualBox on the same machine.

1. On VirtualBox configuration, enable serial communication on port COM1, select "Host Pipe"  for Port Mode, and in "Path/Address" input box type "/tmp/WINCOM1".
2. Start Windows VM
3. From Windows VM, start Hyper Terminal, set speed to 115200 and no Flow control
4. On Linux, open a terminal and type: sudo socat unix-connect /tmp/WINCOM1 TCP4-LISTEN:telnet
5. To transfer file using ZMODEM, open another terminal and type: sz --tcp-client localhost:23 <file to transfer>

To connect to Windows' serial terminal, we simply telnet to localhost: telnet localhost, and amything we type on the telnet terminal will echo back on Windows' HyperTerminal and vice versa.