Unfortunately, there has been some changes in the latest OS Yosemite. Even little things like showing hidden files. To show hidden files in Yosemite, the terminal command is different then 10.9 or lower. It is now the following:

Show Hidden:

defaults write com.apple.finder AppleShowAllFiles -boolean true ; killall Finder

and to hide them:

defaults write com.apple.finder AppleShowAllFiles -boolean false ; killall Finder