radsniff with CSV output

Hi guys, How to run radsniff in order to get csv output from stats? Currently I'm looking at source code (there is no info in help file or man). We have to turn on stats (e.g. -W 5) but when I add -E it just prints help. I'm sure I'm missing something as I'm not very comfortable with C - could you help? I tried: radsniff -x -E -W 5 thanks, Chris