How can I determine the running Mac OS X version programmatically?

Hi everybody,

I have a program which needs to behave slightly differently on Tiger than on Leopard. Does anybody know of a system call which will allow me to accurately determine which version of Mac OS X I am running. I have found a number of macro definitions to determine the OS of the build machine, but nothing really good to determine the OS of the running machine.

Thanks, Joe

From stackoverflow

• I think you can run a *nix system command "uname -a" and parse the results

  Douglas F Shearer : Uname doesn't give the OS version in OS X, only the kernel version.

• In terminal:

  system_profiler SPSoftwareDataType
  

  Gives:

  Software:
  
      System Software Overview:
  
        System Version: Mac OS X 10.5.5 (9F33)
        Kernel Version: Darwin 9.5.0
        Boot Volume: Main
        Boot Mode: Normal
        Computer Name: phoenix
        User Name: Douglas F Shearer (dougal)
        Time since boot: 2 days 16:55
  

  Or:

  sw_vers
  

  Gives:

  ProductName:    Mac OS X
  ProductVersion: 10.5.5
  BuildVersion:   9F33
  

  csexton : And from that I get: `sw_vers | awk '/ProductVersion/ {print $2}'` Very helpful. Thanks.

• See this article here

  But in short, if you're using carbon, use the Gestalt() call, and if you're using cocoa, there is a constant called NSAppKitVersionNumber which you can simply check against.

  Graham Lee : as described in the linked article, checking against NSAppKitVersionNumber isn't so good as it tells you the version of AppKit, not the version of Mac OS X. The two are not linearly correlated.

  Nik Reiman : You should still be able to call Gestalt() from Obj-C code, though.

• The API is through the Gestalt Manager.

  See "Determining OS Version" in the CocoaDev site.

• Is the OS version really what you want? There may be a more appropriate thing to test for, such as the presence of, or version number of, a particular framework.

  Joe Corkery : One of the reason's I am interested in determining which OS version is that support for hardware stereo visualization stopped functioning properly in Leopard, but continues to work in Tiger. Both versions indicate support for it, but only Tiger does it correctly.

• Could you just check for the presence of a capability? For instance:

  if (NSClassFromString(@"NSKeyedArchiver") != Nil)
  

  or

  if ([arrayController respondsToSelector: @selector(selectedIndexes)])
  

  then you know that the operating system does what you need it to do, not that Apple's product marketing group gave it a particular number ;-)

• respondsToSelector: almost certainly is better than you maintaining a table of what given releases do and do not implement.

  Be lazy. Let the runtime tell you whether it can do something or not, and fall back to older methods when you need to. Your code will be far less fragile because you don't have to maintain your own global data that the rest of your code has to keep checking with.

• Run this in the command line:

  system_profiler SPSoftwareDataType | grep Mac
  

• within your program you can use Gestalt. Here is the code I am using for my program to obtain the OS version.

  long version = 0;
  OSStatus rc0 = Gestalt(gestaltSystemVersion, &version);
  if((rc0 == 0) && (version >= 0x1039)) {      
      // will work with version 10.3.9
      // works best with version 10.4.9
      return; // version is good
  }
  if(rc0) {
      printf("gestalt rc=%i\n", (int)rc0);
  } else {
      printf("gestalt version=%08x\n", version);
  }
  

  Peter Hosey : Better to use the separate version-number-component selectors, just in case Apple ever goes over 0xf in either the minor or bug-fix nibble. (They've already gotten up to 0xb in the Tiger series.)

  neoneye : Very good point. gestaltSystemVersionMajor and gestaltSystemVersionMinor. Thank you. will use.