Get under the hood and tweak Yosemite to your heart’s content
Long-term OS X users will be well aware that Terminal hacks can be used to adjust aspects of OS X. Over the years of its existence, the operating system has accumulated a bunch of commands that can be used to make it work better for you. These commands typically start with
defaults write. Most users copy and paste them from a website into the Terminal app, which provides a command line from which to enter Unix commands and interact with OS X. Terminal will feel familiar to older users who remember what it was like before graphical user interfaces became commonplace. Far from being underhand hacks, these hidden settings are created – but often unpublicised – by Apple.
There are more settings available than you are given access to in System Preferences. You can make adjustments to these settings using the defaults command in Terminal. It’s also possible to set values for settings without being limited to the range that’s presented in System Preferences. For example, you can make the Dock huge, and you can completely turn off Mission Control.
Most people copy and paste defaults commands without really realising what it’s doing. There’s nothing wrong with doing that, but it’s important to know how you can reverse the process prior to doing it.
If you want to know what’s going on when you use the defaults command, open Terminal and enter man defaults. Read through the command’s manual by tapping any key, and press q to get back to the command line.
Most tweaks are made by typing defaults followed by write, which tells the command you want to make a change. After that comes the name of the system file containing the preference to change, such as com.apple.
finder or com.apple.dock, and after that comes the name of the preference itself, such as
magnification, followed by the value type
and the new value you want to set – for example,
-boolean true or -integer 128. If you want to see what’s going on inside the .plist files that store preferences, try substituting
read for the command’s write parameter. For example, enter defaults read com.
apple.finder in Terminal to read all the settings for the Finder.
For the most part you’ll enter the commands we present here, or that you find on the internet to change the settings – leave it to OS X experts to discover what commands work in each version.
You should close any app before adjusting its preferences, and if the thing whose behaviour you’re modifying is a fundamental part of OS X, such as the Dock or Finder, you will need to enter a command to relaunch it, such as the notas-scary-as-it-sounds killall finder or killall SystemUIServer.
Here are some useful commands to get you started. To show all files, including system ones that are normally hidden, in the Finder, enter defaults write com.apple.finder AppleShowAllFiles true; killall
Finder followed by ® . To change the format of screen shots, type this
command: defaults write com.apple. screencapture type jpg; killall
SystemUIServer followed by ® . You can substitute jpg, gif, png, pdf or tiff as the value.
Make the Dock comically large by typing defaults write com.apple.dock largesize -int 512; killall Dock followed by ® . Reset it to a sensible size by dragging the Magnification slider in System Preferences > Dock.
Selecting a file in the Finder and pressing the spacebar displays a preview of it. Enter this command and you’ll be able to copy and paste from it: defaults write com.apple. finder QLEnableTextSelection
-bool true; killall Finder and then press the ® key.
Turning on single app mode makes it so that switching to an app will instantly hide all others. While it's not the easiest way to use a Mac, it’s great for concentration. Enter this: defaults write com.apple.dock single-app
-bool true; killall Dock and press ® . Turn it off using the same command again with false at the end instead of true.
There are hundreds of other defaults commands available, and keen Apple fans are often finding new ones. Keep an eye on websites such as defaults-write.com and secrets.blacktree. com to discover fresh commands when a new version of OS X is released.
If you’re reluctant to type commands that modify your Mac’s behaviour, apps such as TinkerTool give you many of the same results.
The defaults command can be used to tweak many behaviours that have no graphical control in System Preferences.