Detect number of CPUs installed

Question

I already found a solution for \"Most unixes\" via cat /proc/cpuinfo, but a pure-Ruby solution would be nicer.

Answer 1

Combination of @grosser's and @paxdiablo's answer, since on my system (winxp) win32_computersystem doesn't have any processor info; this works though:

require 'win32ole'
wmi = WIN32OLE.connect("winmgmts://")
info = wmi.ExecQuery ("select NumberOfCores from Win32_processor")
puts info.to_enum.first.NumberOfCores

To see what's available on your system, run this from powershell (i used 1.0 in this case):

Get-WmiObject -list

(might want to pipe to grep if you've got cygwin installed)