The Dock is, by default, anchored to the middle of the screen. However, in some environments you may want to have it skewed to one side of the screen. In order to do this Apple provides the ability to use pinning. Pinning will pin the dock to the start, end or middle; by default it’s pinned to the middle. If you pin the dock to the start and it’s either on the right or left side of the screen then it will appear to be skewed towards the top. If you pin it to the start and it’s on the bottom then it will skew to the left of the screen. In order to pin the dock to the start you can use the following command:
defaults write com.apple.dock pinning -string start
Once you’ve changed the pinning position you will not immediately see a change. First you need to kill the Dock. You can do this by rebooting or simply using the killall command using Dock as a pattern:
killall Dock
If you pin the dock to the end and it’s either on the right or left side of the screen then it will appear to be skewed towards the bottom of the screen. If you pin it to the end and it’s on the bottom then it will skew to the right of the screen. In order to pin the dock to the end you will use the following command:
defaults write com.apple.dock pinning -string end
To go back to the default settings, just pin the dock to the middle:
defaults write com.apple.dock pinning -string middle
