You can take it with you

If you’ve been looking for a way to share your application data on your Mac between multiple computers, I’ve got a great solution for you. If you’ve been using a Mac for a while you probably know that most of your application data is stored in the Users/YourUserName/Library/Application Support/ApplicationName folder. So, how do you share that data between two or more computers? Simple, you tell all of those computers to reference the same Application Support folder!

Let’s say that you’re using iCal and you want to be able to view/edit your calendar data from any computer easily. Sure, you could publish your calendar and then access it remotely from your other computer, but you wouldn’t be able to make changes to the calendar. Your “hostâ€? computer will stay the same and will be the main storage area for the Application Support folder. Here’s what you do on your second computer (keeping in mind that you’ll need to have personal file sharing enabled on your host computer):

1. Open up the Terminal
2. Navigate to the Application Support folder or your user account.
3. Inside of Application Support you will see a folder called ‘iCal’. Your going to replace that folder with a symbolic link to the shared folder (either accessed on an external drive, or over the network). I use a combination of both. Remove the folder by typing the command rm -Rf iCal
4. Create the symbolic link using this command:
   ln -s /Volumes/Full/Path/To/Shared/App/Support/Folder/iCal [space] iCal

   In my case the name of the host hard drive where my iCal folder is saved is ‘Melody’ so my symbolic link command would look like this:
   ln -s /Volumes/Melody/Users/evanagee/Library/Application\ Settings/iCal [space] iCal

If you’ve done everything correctly you should be able to start up iCal and your calendars will load and you will be able to make changes.

A few notes to keep in mind:

• You should never have the application running on both computers when you’re sharing the application settings folder. Otherwise not all of your changes will be saved when you quit and you risk overwriting changes.
• You can see all of your networked/external drives by visiting /Volumes/ from the command line in Terminal
• With some apps (namely apps who don’t save their data in the Application Support folder) this approach will not work.
• If you wish to use an external drive which you’ll be sharing between multiple computers to store your Application Support data, simply follow the instructions above on ALL computers, and referencing the external drive as the “hostâ€? drive.
• While this does make sure that you have access to the same data in the applications, it does NOT allow both apps to have the same set of preferences. The preference files are stored in a different location and while theoretically you could use this same procedure to share preferences I’ve never tested it, so I can’t recommend it.
• While these instructions won’t work for sharing your iTunes library across multiple Macs, I’ve found a good way to do so and will be posting instructions soon.