How to Use & Customize OS X's Built-in Archive Utility App

Do you ever create what in Mac-speak are Archive files? You know, the handy .zip files that you can create by right-clicking on a file or folder and selecting the option to Compress it? In OS X Tiger and older system versions, the action was called Archive. I'll be using the two terms interchangeably.

For our readers who aren't aware of this feature, or who are new to the concept of file compression for storage and distribution, .zip is as old as the hills. I don't know how old the hills are, but creating compressed files has been around for a very long time. It is a method for taking a single file or folder-full of files and creating a single, space-saving compressed file with a .zip extension. It serves as a container and is recognized universally by other systems. To extract the files and folders from a .zip file, it needs to be expanded

Selecting Compress when right-clicking a folder.

Selecting Compress from the contextual menu will create a .zip file from the original folder.

So, if this feature is "built-in" to OS X, and seamlessly just works, then what is actually doing the work of creating the .zip file and decompressing it to extract the compressed files? One just tends to shrug it off and say something to the effect of, "I dunno … OS X just does it for me."

There are apps which are dedicated to configure, create, and manage these .zip archive files (e.g.; BetterZip available on the App Store), and there are a number of commands and options that the more advanced users out there can issue from the OS X Terminal app. However, the no-nonsense utility installed on your Mac is called Archive Utility. This application is what manages the file compression and expansion activities in OS X.

You are likely to notice Archive Utility appear briefly when expanding a large .zip file. It will pop onto your Dock, then jump off as soon as it's task has completed.

So, where is Archive Utility actually located? If it's an app, then why isn't it located in either the Applications or the Utilities folders? It so happens that there is another folder of system-only "utilities" and other resources hidden away inside the "System Folder" at the root level of your startup drive. It's an out-of-site-out-of-mind kind of thing. In fact, you can't even search for Archive Utility in Spotlight.

One way Archive Utility can be found in Finder is via Go > Computer. Then, select your Mac's start-up drive, then /System/Library/Core Services/. You will see the Archive Utility app listed in there.

The Archive Utility icon.

Archive Utility is found in the CoreServices folder.

Before I continue, I want to cover my backside by first warning you that Apple makes it hard to find and do certain things for a reason. They don't want to spend time on tech support calls just because curious Mac users go in and muck about things that don't concern them! So, while there are several items in the CoreServices folder that can be looked at and perhaps even launched to provide some functionality, I wouldn't advise it unless you know what you're doing!

When launching the Archive Utility app you won't see any windows open up on screen. However, you will see the ARCHIVE UTILITY menu, and it pops onto your Dock. It's a very simple app to use.

In the app's FILE menu, you are able to create an archive (.zip file) manually by selecting individual files or folders. You can't select multiple items to archive. For this you first need to place your files and folders into a single folder which you then select for the archive. The resulting .zip file will take on the name you give that folder. For example, if you have a number of image files stored in a folder called "Vacation Photos", compressing that folder will produce an archive file called "Vacation" Of course, this is also true whether or not you use the Archive Utility to create the archive.

Finally, File > Expand Archive lets you manually select archive files to expand. In this case, you can select multiple archive files when prompted, by using the Shift- or Command-click selection methods.

I know… boooring! Keep going; the interesting features in Archive Utility are found in its Preferences pane.

The Archive Utility Preferences Pane.

I have set up the way I want Archive Utility to treat my archive and original files.

Looking at the Archive Utility preferences pane, the top half governs what actions the app takes when expanding archive files. You can tell Archive Utility where you want expanded files to be saved - either on your local storage drives or on servers and drives on your LAN. You can also indicate what to do with the original archive file. It can be left in place, moved to the trash, or deleted immediately. "Keep expanding if possible" refers to the expansion of embedded archive files.

The bottom half of the Archive Utility preference pane offers you several options for what you want done after compressing a file or folder and where to save the newly created archive file.

By default, when you create an archive file the traditional way - from the desktop - the newly created .zip file will be located in the same directory as the original file or folder. This default behavior cannot be changed. However, you have options when using Archive Utility manually to handle the compression. You can set options for saving the archive files to a location of your choice. This can be anywhere on your local drives or on your LAN. You can also select a new destination for the original uncompressed files, or they can be left alone, moved to the trash, or deleted outright.

Icons representing .zip, .cpgz, and .cpio archive files.

Archive Utility allows you to select which archive format to utilize. The .zip format is the most common format for Mac users.

You can also choose from several archiving formats; the familiar "Zip archive (.zip)", a compression format that is fine for just about anything, the "compressed archive (.cpgz)," and the "regular archive (.cpio)" These last two are formats used typically in the UNIX environment.

Of all of the options that Archive Utility offers, whichever you choose depend on your own workflow requirements and how you store files and archives.

Remember, whatever options you set within the Archive Utility will only apply when working within the app. The default behaviors at the Finder level remain unchanged.

If your workflow and file organization require more flexibility in how and where files are archived and stored by the native OS X compression mechanism, then Archive Utility deserves a look.