Games : Retroarch Missing Config

I installed RetroArch on my Gentoo system successfully. When I run it I get:

four@localhost ~ $ retroarch
RetroArch [WARN] :: system_directory is not set in config. Assuming system directory is same folder as game: "".
RetroArch [ERROR] :: Couldn't find any input driver named "null"
RetroArch [ERROR] :: Fatal error received in: "find_input_driver()"
four@localhost ~ $ 

However, there is no config file to set these. I looked at the retroarch commands and did not see any command to create a default config file. Any suggestions?