5 Replies Latest reply: Jun 13, 2012 12:32 PM by BobHarris
medv4380 Level 1 Level 1 (0 points)

Is their a way to block all 64-bit apps.  I know how to change them for individual apps, but is their a way to make it so that the OS ignores the fact that their is a 64bit enabled processor and run like it's a 32 bit processor.


I'm attempting to troubleshoot a program that I'm aware has issues if it gets any data related to 64 bit code and I'm aware it does memory walks, and I would like to remove any and all 64bit apps that are running to remove them as a variable.


The Kernel is already in 32 bit mode.

MacBook, Mac OS X (10.6.8)
  • X423424X Level 6 Level 6 (14,215 points)

    Booting up in 32-bit isn't sufficient?


    OS X: Starting up with the 32-bit or 64-bit kernel

  • Kurt Lang Level 8 Level 8 (35,970 points)

    Even though the kernel is running 32 bit, every other piece of the OS is running 64 bit. You can check that under the Software > Applications heading in the System Profiler. There is no way to turn it off. So you're dealing with far more than your third party apps, in regards to those running 64 bit.

  • medv4380 Level 1 Level 1 (0 points)

    With a 32 bit Kernel OSX will allow 64bit apps to run as long as you have a 64bit processor.  If you have one you'll notice apps in Activity Monitor are in 64bit mode.  This is different in other OSes like Linux and Windows where a 32bit kernel won't run 64bit apps.


    Linux has a SetArch command that can be used to force an application to run in other archetecures like i386, but it doesn't look like Apple has one, or at least not by the same name.


    From what I know of the App that I'm testing if it is told that their is 8 gigs of ram it will try to scan 8 gigs of ram and lock up even if it's running in 32bit mode.  Since I know that's an issue already I'm trying to weed out any other issues by boxing it in further.

  • X423424X Level 6 Level 6 (14,215 points)

    Makes sense that booting in 32-bit mode would only affect addressing. 

  • BobHarris Level 6 Level 6 (16,480 points)

    I do not know of a configuration way (there could be one, I've never bothered looking).


    However, maybe you could remote (or protect) some critical 64-bit framework/run-time-library that all 64-bit apps need. If it is no longer available, the 64-bit apps would not be able to run.


    use Applications -> Utilities -> Terminal and the 'lsof' command to find out what files are always opened by all the 64-bit apps, then track them down and see if any are 64-bit specific and make them not available.