Obtain hw.model from the sysctl tool

Saves building our own tool to do the same job!

Library/Homebrew/hw.model.c

@@ -1,17 +0,0 @@
-/*
-   This software is in the public domain, furnished "as is", without technical
-   support, and with no warranty, express or implied, as to its usefulness for
-   any purpose.
-*/
-#include <sys/sysctl.h>
-#include <stdio.h>
-
-int main()
-{
-    char buf[32];
-    size_t sz = sizeof(buf);
-    int r = sysctlbyname("hw.model", buf, &sz, NULL, 0);
-    if (r == 0) 
-        printf("%.*s", sz, buf);
-    return r;
-}

Library/Homebrew/hw.model.rb

@@ -21,13 +21,12 @@
 #  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 #  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
+
+# The output of the command is in the form of: `MacBook2,1'
+# This yields: "MacBook", 2, 1
 def hw_model_output
-  require 'fileutils'
-  HOMEBREW_CACHE.mkpath
-  exe=HOMEBREW_CACHE+'hw.model'
-  Kernel.system "gcc -Os #{File.dirname __FILE__}/hw.model.c -o #{exe}" unless exe.file?
-  /(.*)(\d+),(\d+)/ =~ `#{exe}`
-  yield $1, $2.to_i, $3.to_i
+  model=`/usr/sbin/sysctl hw.model`.match /hw.model: (\w+)(\d+),(\d+)/
+  yield model[1], model[2].to_i, model[3].to_i
 end
 
 # http://support.apple.com/kb/HT3696
@@ -36,10 +35,10 @@ def hw_model
   hw_model_output do |model, major, minor|
     case model
       when "iMac"
-        if major <=4
+        if major <= 4
           :core1
         else
-          $unknown_hw_model=true if major >8
+          $unknown_hw_model=true if major > 8
           :core2
         end