YUI compressor - compress multiple input files into one output file

Question

Possible Duplicate:
How can I combine and compress multiple script and css files for production use?

I would like to compress multiple javascript files into one minified file. I'm using YUI Compressor. On their page it says that it can do it like so (their example uses css files but I replaced it with js):

java -jar yuicompressor.jar -o '.js$:-min.js' *.js 

When I try to execute this I get an empty file named .js$

What am I missing?

Solution

The following works for me: java -jar yuicompressor.jar *.js > combined.js