Testing for Rosetta use in OS X

With speculation and rumor suggesting (possibly accurately) that OS X Lion will be issued without the "Rosetta" dynamic translator that allows PowerPC code to run on Intel-based Macs, a number of people are undoubtedly concerned about their readiness to use a platform without any form of PowerPC support. Over the years, people have accumulated applications, tools, and utilities that use either Intel or PowerPC, or both, and while numerous developers have updated their software to work natively on Intel Macs, with Rosetta being so transparent, people may be unsure whether their software requires PowerPC.

Another factor that plays into this is even though Rosetta applications will run slower than their native counterparts, some Mac systems are fast enough to compensate for any noticeable speed difference.

If a program does require PowerPC and you install OS X without Rosetta, you will see the program's icon appear with a white "no entry" slash through it, and you will not be able to open the program. To avoid chancing that this will happen with any of your current programs, it will help to check whether any that you use or have installed are PowerPC-only applications.

There are several ways to do this in OS X:

1. Finder info windows
   The first method to see an application's architecture is to get information on it in the Finder. Select the application and press Command-I and look in the "General" section of the window. You should see the line "Kind: Application" followed by the architecture in parentheses. For some universal binary applications, you may also see an option in this window to open the application using Rosetta.

   While the Finder information window is useful, you would have to check each application file separately, which might take a long time.

2. System Profiler
   Apple's System Profiler utility is perhaps the best method of checking your installed applications' architectures. Open the utility (located in the /Applications/Utilities/ folder) and select "Applications" under the "Software" section. The list may take a few moments to populate, but when it is complete you can sort the list by Kind, which should be either Universal, Intel, PowerPC, or possibly "Classic." From here you can check to see if any PowerPC applications are ones you frequently use, and see if an updated version is available.

3. Activity Monitor
   While System Profiler will list all applications on your system, you can use Activity Monitor to see if any (including background tasks) are PowerPC as well. To do this, launch Activity Monitor and press Command-1 to bring up the main Activity Monitor window if it does not show by default. When displayed, check to see if a column titled "Kind" is present, and if not then enable it by going to the View > Columns menu. With the "Kind" column enabled, click it to sort the running applications and processes by kind, and check the list to see if any are PowerPC applications.

With the applications identified, you can check to see if the developer has a native Intel version available, or if you do not need or use the program you can remove it from your system. Many times developers may include obsolete tools with large application packages that are not necessary for the majority of that package's functions, so if you see a helper utility that is PowerPC only, then do not be alarmed as long as the remaining package applications contain Universal or Intel code.

Finally, when OS X 10.7 Lion is released, Apple will still continue to support OS X 10.6 so there is no need to rush to upgrade your OS software. OS 10.6 should still work fine for a number of years after Lion is released, so unless you need the new features that Apple is including with Lion, then you might consider waiting if some of your applications still require Rosetta. Lastly, keep in mind that there will likely be a break-in period for OS X 10.7, so even if you are keen on upgrading soon you might wait while initial bugs in the OS are ironed out.

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