Thanks to ever-growing hard-drive capacities and ever-faster network connections, compressing files isn’t quite the vital and frequent task it used to be. Still, it’s useful in certain situations; for example, when attaching files to an email message, when trying to fit 700MB of data onto a 512MB flash drive, or when copying files to a server or drive that doesn’t support Mac OS X metadata.
There are plenty of options for compressing files in OS X, many of them free. The Finder’s own Create Archive command creates .zip archives that preserve Mac resource forks and other information; those who’ve purchased the $80
can create similar, but more efficient, StuffIt archives; and those versed in Terminal have access to several built-in command-line compression utilities, such as
But if you do most of your file-exchanging with Windows, Linux, or Unix users, these options aren’t the best for your recipients. Preserving Mac resource forks, .DS_Store files, and other invisible data is great for Mac users, but all of this data is unusable by other operating systems. As a result, when a non-Mac-using recipient uncompresses your archive, the legitimate files will be accompanied by a good deal of virtual litter. (I talked about this issue when I covered
; $10) is a handy tool for those who frequently file-exchange with users of computers other than Macs. In addition to providing a dead-simple way to compress files in one of multiple formats, it’s also the easiest way I’ve found to automatically remove the extraneous data noted above when sending files to users of other operating systems.
If you’re copying data to a server or saving it for later, click on the Compress button in Compress Files’ main window; if you’re sending the data via email, click on Email. In either case, your options are the same:
To omit Finder “Desktop” files—.DS_Store and similar—from the resulting archive, check the “Omit Finder Desktop files” box; to omit resource forks (which can appear to non-Mac users as near-duplicate, but smaller, versions of every file), check the “Omit Mac-specific content files” box.
The first time you check one of these boxes, Compress Files alerts you to what each actually does; for example, here’s the dialog that appears after checking the “Omit Mac-specific content files” box:
(As a side note, one other benefit of omitting these various files when sending data to non-Mac users is that the resulting archive will be smaller. Sometimes only minimally, but other times surprisingly so.)
You can also choose to automatically delete the original files after the archive is created. Finally, choose the type of archive: .zip, .tar, .tar.gz, .tar.bz2, or .dmg. (The latter is a Mac OS X disk image; you can choose between compressed or encrypted options. You should avoid these formats when sending to non-Mac users, but they’re useful when exchanging files between Macs; Compress Files makes creating such images quick and easy.)
Once you’ve chosen your options, simply drag the files and folders you want to compress into the Compress Files window; compression begins immediately. (I initially found this behavior—setting your options first and
dragging your files into Compress Files—confusing.) In the future, you can also drag files directly onto the Compress Files application icon, which uses the most-recently-used options and settings when compressing. This is a convenient approach if you tend to use the same options frequently.
If you chose Compress Files’ Compress screen, the resulting archive will be saved in the location you set in Compress Files’ preferences: on the Desktop or another default folder of your choosing, in the same folder as the originals, or in a folder you chose when you dragged the files into Compress Files. (An option in the preferences dialog can prompt you to name the archive; otherwise Compress Files names the archive for you.) If you were using the Email screen, the archive is saved but then your default email application will open, a new message will be created, and the resulting archive will be attached.
Compress File’s Archive screen lets you create archives and then save them to a particular location—for example, to a folder of archived files on your own Mac, or to a shared directory on a network server. (Unfortunately, Compress Files doesn’t include any FTP functionality, so it can save files only to a network volume already available in the Finder.) This is a useful feature for creating an archive of archives; however, because it’s designed for keeping backups of your own data, rather than for sending files to other people, compressing files via the Archive screen
Finder- and Mac-specific data.
Compress Files’ documentation is sparse (some of the options in the preferences dialog don’t appear to be documented anywhere); its progress bar doesn’t really show any progress; and, as I mentioned above, I wish it could automatically copy files to FTP and other remote servers. But if you frequently exchange files with people who aren’t lucky enough to work on a Mac, Compress Files helps you be more considerate. It also makes it easy to create archives in various formats.
Compress Files requires Mac OS X 10.4 or later and is a Universal Binary.