metric/system/numcpu/cpu_windows.go

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//
//     http://www.apache.org/licenses/LICENSE-2.0
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package numcpu

import (
	"fmt"

	"golang.org/x/sys/windows"
)

// getCPU implements NumCPU on windows
// For now, this is a bit of a hack that just asks for per-CPU performance data, and reports the CPU count
func getCPU() (int, bool, error) {
	numCPU := windows.GetActiveProcessorCount(windows.ALL_PROCESSOR_GROUPS)
	if numCPU == 0 {
		return -1, false, fmt.Errorf("received an error while fetching cpu count: %w", windows.GetLastError())
	}
	return int(numCPU), true, nil
}