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Dec '08

Installing sys-cpu 0.6.0 on OS X 10.5 Leopard

posted by delano

I was trying to install the sys-utils Ruby libraries today and got an error while building sys-cpu on OX 10.5 Leopard. sys-cpu is a multi-platform Ruby library for accessing information about the CPUs and it contains a native extension which needs to be compiled during them installation. This is the error:

$ sudo gem install sys-cpu
  Building native extensions.  This could take a while...
  ERROR:  Error installing sys-cpu:
  ERROR: Failed to build gem native extension.
  cpu.c:14:17: error: kvm.h: No such file or directory
  cpu.c:14:17: error: kvm.h: No such file or directory
  cpu.c: In function 'cpu_load_avg':
  make: *** [cpu.o] Error 1

OS X 10.5 seems to be missing a C header file, kvm.h, that's required by sys-cpu. Here's how you can solve the problem:

  • Download a non-gem version and unpack it.
  • Get a copy of kvm.h. If you're running OS X 10.5 that was upgraded from 10.4, you can find it in /Developer/SDKs/MacOSX10.4.sdk/usr/include. If not, you can download it from here:
  • Copy kvm.h in to sys-cpu-0.6.0/ext
  • Inside of sys-cpu-0.6.0, run: rake test then sudo rake install
  • The following command should now run without errors: ruby -r'sys/cpu' -e 1.

That's it!

I'm Delano Mandelbaum, the founder of Solutious Inc. I've worked for companies large and small and now I'm putting everything I've learned into building great tools. I recently launched a monitoring service called Stella.

You can also find me on:

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Solutious is a software company based in Montréal. We build testing and development tools that are both powerful and pleasant to use. All of our software is on GitHub.

This is our blog about performance, development, and getting stuff done.

-       Solutious