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

Surely if you can cat it, you can open, read and close it using the standard features of the language without resorting to a system()-type call.

You may just need to detect what platform you're on dynamically and either:

• use the /proc/cpuinfo "file" for Linux; or
• communicate with WMI for Windows.

That last line can use:

require 'win32ole'
wmi = WIN32OLE.connect("winmgmts://")
info = wmi.ExecQuery ("select * from Win32_ComputerSystem")

Then use info's NumberOfProcessors item.