code: func GetMTU(name string) (uint32, error) {
  	fd, err := syscall.Socket(syscall.AF_UNIX, syscall.SOCK_DGRAM, 0)
  	if err != nil {
  		return 0, err
  	}
  
  	defer syscall.Close(fd)
  
  	var ifreq struct {
  		name [16]byte
  		mtu  int32
  		_    [20]byte
  	}
  
  	copy(ifreq.name[:], name)
  	_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, uintptr(fd), syscall.SIOCGIFMTU, uintptr(unsafe.Pointer(&ifreq)))
  	if errno != 0 {
  		return 0, errno
  	}
  
  	return uint32(ifreq.mtu), nil
  }
docs: // GetMTU determines the MTU of a network interface device.