How to multitask in OS X Lion's recovery partition
Apple's Recovery partition for OS X Lion contains a number of utilities, but you can only open one at a time. Here is how to open multiple utilities at the same time to ease your troubleshooting and recovery routines.
As with prior versions of OS X, the recovery option in Lion is a fairly stripped-down version of the OS that has a few tools for managing your system. This allows the recovery tools to load quickly and be available, but in its simplicity Apple's recovery system has been a bit cumbersome in that it will by default only run one recovery tool at a time.
For instance, if you boot to the Lion Recovery HD partition and then launch Disk Utility, the installer will quit and only Disk Utility will run. Additionally, Lion's recovery partition now contains Safari so you can browse the Web for help, but if you are using Safari to get help then you undoubtedly are going to be using other tools such as the Terminal and Disk Utility to run the various tasks needed to fix your system. However, with the default of running one tool at a time, you will need to run Safari, write down the information you need (since Lion's recovery partition does not contain a print system), and then proceed with whatever fix routine you are attempting.
This may be frustrating, especially since OS X is a multitasking OS and should be able to launch and handle multiple programs at the same time. Luckily, there is a way around this limitation, because Apple supplies the Terminal in the recovery partition and this tool will allow you to run various other programs concurrently. Here is how to do this:
Boot to the recovery partition
The first step is to boot to the recovery partition by holding the Option key when the system starts and then selecting the Recovery HD disk when it appears in the boot menu. Alternatively, you can boot with Command-R held down to immediately go to the recovery partition without using the boot menu. When the recovery system loads, select your language to get to the main utilities screen.
Open the Terminal
Go to the Utilities menu and select the Terminal. Since OS X applications can be launched from the Terminal, you will use multiple instances of the Terminal to manage multiple programs at the same time. By default one Terminal window will open, but you can launch multiple Terminal sessions by pressing either Command-N for a new window, or Command-T for a new tab in the current window.
Launch a program
OS X application packages cannot be launched directly since they are merely folders that are recognized as containing applications (and required resources) because they have ".app" appended to their names--in essence you can make any folder appear like an application by renaming it with .app at the end of its name. The actual executable file within an application package is in the /Contents/MacOS/ subdirectory, so you will need to target this executable with the Terminal to launch the program.
For instance, to open Safari you will need to run the following command, which will point to the Safari executable within the Safari application package on the recovery partition:
When you see the program launch, the Terminal may fill with a bunch of warnings and messages--these messages are the standard output of the program, and can usually just be ignored. Do not close the Terminal window, or the program you have opened will immediately shut down, since it is a child process of the Terminal window.
Launch a second program
If you have launched Safari using the command above, go back to the Terminal window and generate a new one. Then run any of the following commands to launch the respective utility:
Disk Utility: /Applications/Utilities/Disk\ Utility.app/Contents/MacOS/Disk\ Utility
Firmware Password Utility: /Applications/Utilities/Firmware\ Password\ Utility.app/Contents/MacOS/Firmware\ Password\ Utility
Network Utility: /Applications/Utilities/Network\ Utility.app/Contents/MacOS/Network\ Utility
RAID Utility: /Applications/Utilities/RAID\ Utility.app/Contents/MacOS/RAID\ Utility
Reset Password: /Applications/Utilities/Reset\ Password.app/Contents/MacOS/Reset\ Password
Startup Disk: /Applications/Utilities/Startup\ Disk.app/Contents/MacOS/Startup\ Disk
System Information: /Applications/Utilities/System\ Information.app/Contents/MacOS/System\ Information
Terminal (redundant): /Applications/Utilities/Terminal.app/Contents/MacOS/Terminal
These commands are the full file path to the executable file within the application package, and while the standard OS X Terminal contains an "open" command that can simplify the launch of programs, this command is not available in the Lion Recovery partition, so you will have to use the long version to launch the programs of interest.
Using Tab completion
These commands are essentially just full folder paths to the executable for the respective program, and it may seem a bit much to remember all of them in their entirety, so you can use the Terminal's Tab-completion feature to help locate each of them. Tab completion means you can start the beginning of a command, folder path, or file name, and then press Tab and the Terminal will fill out the remainder of the command based on the options available to it, until it finds a point at which it needs you to clarify which direction to go.
To use Tab completion, type a single forward slash and then press the Tab key (nothing should happen). What you have done here is specified the root of the filesystem, but there are multiple items here, so the Tab-completion does not know what to choose. If you press the Tab key again then the Terminal will list all of the possibilities, of which one will be the Applications folder. You can now continue the command by typing "Applications," or you can just type the first few letters of it and press Tab to have the Terminal complete that folder name for you. Do so (note that commands and file paths in the Terminal are case-sensitive), and you will see the name /Applications/ show up. You can now press the Tab key again to make the Terminal list the options available, and you will see the Safari.app application package and the Utilities folder.
Now type "Uti" followed by the Tab key, and you will see the command fill out so it reads "/Applications/Utilities/." If you press Tab a second time without entering any new characters, the Terminal will list all the possibilities based on the command that has currently been entered, so doing this will list all items in the /Applications/Utilities/ directory (which are the various programs you are trying to open). From here you can enter the first few characters of the desired program name, and continue hitting Tab until you fill out the full path to the executable file in the /Contents/MacOS/ subdirectory. Then press Enter and the program will launch.
Tab completion may take some getting used to if you are not familiar with it, but it can be a great help when you need to use the Terminal. If you do not care to use Tab completion, then you can write down the full commands listed above and type them exactly into the Terminal to launch the associated programs.
Uses for multitasking
Access the Web to find resources when troubleshooting.
Using Safari you can read through sites like MacFixIt or the Apple Support Communities for guidance on fixing your Mac, while keeping the Terminal, Disk Utility, and other tools open at the same time for easy access.
Access Unix manual pages for Terminal commands.
One feature that Apple did not include in the Recovery HD partition is the Unix manual pages, aka man pages, which contain the syntax and options for most of the Terminal commands on the system. Even the most Terminal-savvy users will frequently check the manual pages for command options, so having this missing can be a bit of a burden. Using multitasking you can look up the command man pages online, and keep the window open next to an available Terminal window for running the command.
Multiple applications at your service
Having multiple applications open means quick access to their functionality, instead of having to quit each one in order to open the next. If you are troubleshooting network setups then you can have Network Utility open along with Safari and the Terminal. If you are troubleshooting your hard drives then you can have RAID Utility open along with Disk Utility, while looking up instructions in Safari.