CrossOver: Windows apps without Windows

CodeWeaver's CrossOver Mac allows many Windows applications to be installed and run directly on Mac OS X

VirtualBox may be free, but you still have to own a copy of Windows. If you're not willing to shell out a few hundred dollars to Microsoft but still want to run Windows on your Intel-based Mac, there is one more alternative: CrossOver from CodeWeavers costs $40 and runs Windows applications on Mac OS X -- without Windows.

CrossOver is not virtualization, as evidenced by the whimsically named technology behind it: the open source Wine (Wine Is Not an Emulator) project. With CrossOver, Windows applications run directly in Mac OS X, and not in a virtual machine. Wine is an implementation of the Win32 API on Mac OS X. The Windows applications don't know they're not running on Windows. There's also a CrossOver for Linux.

The result is that a Windows application running with CrossOver uses fewer system resources, including memory, disk space, and CPU utilization, than the same app running in Parallels Desktop or VMware Fusion. Performance of Windows applications is very good.

[ Parallels Desktop 5, VMware Fusion 3, or VirtualBox 3.1? See "InfoWorld review: Windows on the Mac." ]

Parallels Desktop and VMware Fusion can hide the Windows desktop and enable you to move data between the Windows and Mac environments, but they still use Windows' NTFS file system in the form of a virtual C: drive. With CrossOver, Windows apps share the Mac's file system. CrossOver lets you launch not only Windows files, but also Windows applications, directly from the Mac OS X Finder. CrossOver doesn't hide Windows -- it jettisons the operating system.

There is a catch, however: Not all Windows applications run in CrossOver. In fact, quite a few don't. That's because CodeWeavers and the Wine developers tweak Wine for specific programs.

CodeWeavers makes no bones about this trade-off. On its Web site, the company says that CrossOver "runs some Windows applications very well, some so-so, and some not at all." The company Website has an extensive list of Windows applications rated gold, silver, bronze, and "known not to work," according to how well they run in Mac OS X and Linux with CrossOver. When you install CrossOver, the software tells you which Windows applications are supported.

[ Wine is in InfoWorld's Open Source Hall of Fame. See "The greatest open source software of all time" and "Top 10 Open Source Hall of Famers." ]

With each new build of CrossOver, CodeWeavers focuses on the Windows applications that users say they want to run. The CodeWeavers Website lets you vote for the applications that you want to see working better. As of this writing, the game Left 4 Dead (Steam) was No. 1; Internet Explorer 8 was No. 5.

CrossOver comes in two versions: CrossOver and CrossOver Games, each in Mac and Linux versions. CrossOver focuses on optimizing Windows business applications to run. CrossOver Games is optimized for gaming. CodeWeavers also offers a bundle that includes both, CrossOver Professional ($70), which also comes with a year of tech support.

CodeWeavers promises a major new version during the first part of this year, CrossOver 9. The company said that the upgrade will run more Windows applications, and it will do so more cleanly. The new version will focus on improving support of Internet Explorer and Microsoft Office, including fuller support for Excel macros and other smaller Office features. There will also be a user interface revamp.

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