To show hidden files on Mac OSX:
1. open terminal
2. type: defaults write com.apple.finder AppleShowAllFiles ON
To undo:
1. type: defaults write com.apple.finder AppleShowAllFiles OFF
1. open terminal
2. type: defaults write com.apple.finder AppleShowAllFiles ON
To undo:
1. type: defaults write com.apple.finder AppleShowAllFiles OFF