IO_OBJECT_NULL 22 base/mac/scoped_ioobject.h explicit ScopedIOObject(IOT object = IO_OBJECT_NULL) IO_OBJECT_NULL 31 base/mac/scoped_ioobject.h void reset(IOT object = IO_OBJECT_NULL) { IO_OBJECT_NULL 61 base/mac/scoped_ioobject.h object_ = IO_OBJECT_NULL; IO_OBJECT_NULL 1066 third_party/libusb/src/libusb/os/darwin_usb.c *usbInterfacep = IO_OBJECT_NULL; IO_OBJECT_NULL 1142 third_party/libusb/src/libusb/os/darwin_usb.c io_service_t usbInterface = IO_OBJECT_NULL; IO_OBJECT_NULL 103 third_party/libusb/src/libusb/os/darwin_usb.h #if !defined(IO_OBJECT_NULL)