The serial output is a little confusing at first.
When you upload your sketch, any serial console will be shutdown. You will have to open the serial console again. The problem is, by the time the console is open again, your sketch has finished, and is no longer printing anything out.
The fix for this is to reset the sketch. On the galileo board press the reset button, and your sketch will run again, and the serial console will stay open so you can capture the print from the sketch. (Note: do not press the reboot button, that restarts the Linux system, which takes a minute or so to complete, and will kill your serial console)