How to detect an Apple Silicon system from an x86_64 process?

Question

Hi,

i'm looking for a way to detect, from an x86_64 executable (ostensibly running in Rosetta), whether the architecture of the current system is arm64.

Unfortunately, it seems even calling out to "/usr/bin/uname -m" via TSTask does not work, as uname seems to return "x86_64" the called from a x86_64 process, even on Apple Silicon (it returns arm64 as expected, when the calling process is arm64 too).

Is this as designed, or a bug? And does anyone have an alternative suggestion to safely detect the system architecture?

macOS
AppKit

1.5k

Posted by

dwarfland

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Answer 1

https://developer.apple.com/documentation/apple_silicon/about_the_rosetta_translation_environment?language=objc#3616845

Determine Whether Your App Is Running as a Translated Binary

On Apple silicon, a universal binary may run either natively or as a translated binary. The system runs the native version whenever possible, but the user might opt to run the code using Rosetta to support older plug-ins.

To programmatically determine when a process is running under Rosetta translation, call the sysctlbyname function with the sysctl.proc_translated flag, as shown in the following example. The example function returns the value 0 for a native process, 1 for a translated process, and -1 when an error occurs.

Code Block cint processIsTranslated() {
   int ret = 0;
   size_t size = sizeof(ret);
   if (sysctlbyname("sysctl.proc_translated", &ret, &size, NULL, 0) == -1) 
   {
      if (errno == ENOENT)
         return 0;
      return -1;
   }
   return ret;
}

Posted by

dwarfland

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Answer 2

https://developer.apple.com/documentation/apple_silicon/about_the_rosetta_translation_environment?language=objc#3616845

Determine Whether Your App Is Running as a Translated Binary

On Apple silicon, a universal binary may run either natively or as a translated binary. The system runs the native version whenever possible, but the user might opt to run the code using Rosetta to support older plug-ins.

To programmatically determine when a process is running under Rosetta translation, call the sysctlbyname function with the sysctl.proc_translated flag, as shown in the following example. The example function returns the value 0 for a native process, 1 for a translated process, and -1 when an error occurs.

Code Block cint processIsTranslated() {
   int ret = 0;
   size_t size = sizeof(ret);
   if (sysctlbyname("sysctl.proc_translated", &ret, &size, NULL, 0) == -1) 
   {
      if (errno == ENOENT)
         return 0;
      return -1;
   }
   return ret;
}

Posted by

dwarfland

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Answer 3

Same problem with you. No answer yet.
All solutions not work for an App run in Rosetta.

Posted by

Sid8ur6yw3

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How to detect an Apple Silicon system from an x86_64 process?

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