In Linux, you can use rsync to synchronize files in multiple directories. I am looking for the equivalent in the Windows world. This is my user case:

1. I have a usb flash drive to carry files around;
2. I have fixed number of directories on a Windows machine from where I save and edit important script, source code, and other files;
3. I can create the same directory structure on my usb flash drive, if needed. The usb has 1 gb capacity;
4. In almost all cases, files on the Windows machine are more recent.

I want a simple program that update all files in the usb drive, so that they are in sync with those on the Windows workstation. Ideally, the program should be lightweight and has a command line interface.

Any recommendations? Or maybe I should write one for myself. This could be a good project for me to fulfill my wish of being a functional C programmer.