I`m stuck with GetSystemTimes function. There is no any problem in c++ code, but with golang I'm getting three nils instead of expected values
My code:
package main
import (
"log"
"syscall"
"unsafe"
)
var (
modKernel32 = syscall.NewLazyDLL("kernel32.dll")
procGetSystemTimes = modKernel32.NewProc("GetSystemTimes")
)
type SystemTimes struct {
IdleTime *syscall.Filetime
KernelTime *syscall.Filetime
UserTime *syscall.Filetime
}
func main() {
times, err := getSystemTimes()
if err != nil {
log.Fatal(err)
}
log.Printf("idle=%v, kernel=%v, user=%v", times.IdleTime, times.KernelTime, times.UserTime)
}
func getSystemTimes() (times SystemTimes, err error) {
res, _, err1 := procGetSystemTimes.Call(uintptr(unsafe.Pointer(times.IdleTime)), uintptr(unsafe.Pointer(times.KernelTime)), uintptr(unsafe.Pointer(times.UserTime)))
if res != 1 {
return times, err1
}
return
}
It's super simple and very similar to syscall`s GetProcessTimes function from stdlib. And look, what my program prints:
idle=<nil>, kernel=<nil>, user=<nil>
Why? I expect error or result, why my fields are empty?
Confguration: win8 x64, go1.4.2 windows/amd64
You're passing the address of nil fields to the function.
Either make it point directly to the Filetime
struct or initialize all 3 fields before passing them:
type SystemTimes struct {
IdleTime syscall.Filetime
KernelTime syscall.Filetime
UserTime syscall.Filetime
}
.....
res, _, err1 := procGetSystemTimes.Call(uintptr(unsafe.Pointer(×.IdleTime)), uintptr(unsafe.Pointer(×.KernelTime)), uintptr(unsafe.Pointer(×.UserTime)))
Output:
┌─ oneofone@Oa [/tmp]
└──➜ env CC=i686-w64-mingw32-gcc CGO_ENABLED=1 GOOS=windows GOARCH=386 go build -a /tmp/syscall.go; and wine syscall.exe
2015/05/09 22:31:53 idle={1292275456 39}, kernel={1436840864 41}, user={3496565408 2}