Mac tips (not only) for switchers

[2011-03-22] apple, hack, computers, mac

If you are new to the Mac, everything can feel a bit off. This post tries to help. And might even teach you something new if you are already familiar with the Mac. I am also mentioning some advanced things which should be interesting for programmers and people coming from Linux.

Terminology

Option key ⌥: Mac speak for “Alt”.
Command key ⌘: Used for menu commands.
Aqua: The name of the Mac OS X GUI. Meaning: You can usually substitute “GUI” for “Aqua”, sometimes also used to differentiate X11-based programs from true Mac OS X programs.
Cocoa: An object-oriented API for writing Mac OS X programs, inherited from the NeXT operating system. A variant of Cocoa, Cocoa Touch is used on iOS devices (which run a port of Mac OS X).

File System

Applications: Mac applications are just directories whose name ends with “.app”, in the Finder, you can use the context menu to look inside such a folder.

Thus, one can easily bundle files with an application. This was used when Apple switched from PowerPC processors to Intel processors to include binaries for both architectures in a single application.
Applications are easy to install and uninstall: You just copy them wherever you want to use them and trash them for deinstallation. Alternative ways of installing are via Installer packages and the Mac App Store.

File system layout: Inspired by the Unix /usr/bin etc., but a bit easier to understand.

Mac OS X: Where The Files Belong Now

Hidden files: Under the Finder (but not under the shell) much of Mac OS X's Unix personality is hidden. Similarly to Unix, files whose names start with a dot are not shown in the Finder.

Mac OS X Hidden Files & Directories

Terminal

Use an Option click to position the cursor in the terminal, e.g. when you are using emacs over ssh.
Open files with Mac applications:

open . # open the current directory with the finder
open -a textedit myfile.txt
open -a textedit # just open the program

Drop files on a Terminal window to paste their path.
ssh-agent: Already runs for the complete session (including all GUI apps). Thus, you only need to ssh-add your keys (via Terminal).

GUI, various apps

Drag and drop

D&D and Option-Tab: You can use Option-Tab during D&D, in order to easily transfer data between programs.

D&D a file on Mail.app: Creates a new email message whose attachment is the file.

Finder: Command-clicking on a window title gives you a list of folders enclosing the current one.
Sleep display:

Put the cursor in a hot corner. Use “System Preferences → Desktop + Screen Saver → Hot Corners” (or search for “corner”) to configure a corner so that the display is put to sleep if the cursor stays in it.
Type Ctrl-Shift-Eject

Keyboard and keyboard shortcuts

Mac OS X has many keyboard shortcuts [4].
Many Emacs key bindings work in Mac applications (Ctrl-A, Ctrl-E, Ctrl-K, etc.)
Keyboard and character viewer menu: can be enabled via the “Keyboard” preference pane. Allows you to access characters such as arrows from any application.
Use F1, F2, etc. as function keys: Helpful if you develop with an IDE, enabled via the “Keyboard” preference pane.
Command key combinations and dialog windows: In some cases, you can use a Command key combination to click a button. For example: When you are in danger of overwriting a file, a dialog appears and you can use Command-R to replace or Command-D for “Don’t Save”.
Shut down dialog: activate via Ctrl-Eject, type the initial character of any of the buttons to click them.

Making screen shots

Including a mouse pointer in the shot: This is where the “Grab” application helps.
Entire screen, window, selection: See Preview.app, menu “File” which has a submenu for screenshots.
Entire screen: Command-Shift-3
Selection: Command-Shift-4

Benefit: Can also be used to count pixels on screen
Variation: Hit space and get a cursor that selects a window to be shot.

Spotlight [5]

Activate via Command-Space
Calculations: addition, multiplication, etc. Even sin and cos work. [6]
Filter by file type: For example, “kind: pdf”.
Phrases: Put words that should appear in a given order, next to each other, in quotes.
Exclude folders: Use the Spotlight preference pane to hide some folder from indexing and appearing in search results.

Enabling Hidden Features in Apple's Programs. Apple's apps store their preferences quite cleverly in a tree that can be accessed from the command line. Thus, the following hacks are possible. Close the application before performing them.

iTunes: By default, the Ping button transports you to the iTunes store. Option-click instead gets you to your own library. The following preference makes the latter the default.
- In Terminal type: defaults write com.apple.iTunes invertStoreLinks -bool YES
Safari: Enable the debug menu (which has some nifty stuff in it, you can e.g. change the user agent)
- Type: defaults write com.apple.Safari IncludeDebugMenu 1
Terminal: Enable focus-follows-mouse
- Type: defaults write com.apple.Terminal FocusFollowsMouse -string YES

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