USB_BUS_STATISTICS_0 structure (usbuser.h)
The USB_BUS_STATISTICS_0 structure is used with the IOCTL_USB_USER_REQUEST I/O control request to retrieve bus statistics.
Syntax
typedef struct _USB_BUS_STATISTICS_0 {
ULONG DeviceCount;
LARGE_INTEGER CurrentSystemTime;
ULONG CurrentUsbFrame;
ULONG BulkBytes;
ULONG IsoBytes;
ULONG InterruptBytes;
ULONG ControlDataBytes;
ULONG PciInterruptCount;
ULONG HardResetCount;
ULONG WorkerSignalCount;
ULONG CommonBufferBytes;
ULONG WorkerIdleTimeMs;
BOOLEAN RootHubEnabled;
UCHAR RootHubDevicePowerState;
UCHAR Unused;
UCHAR NameIndex;
} USB_BUS_STATISTICS_0, *PUSB_BUS_STATISTICS_0;
Members
DeviceCount
The number of devices on the bus.
CurrentSystemTime
The current system time.
CurrentUsbFrame
The number of the current USB frame.
BulkBytes
The amount, in bytes, of bulk transfer data.
IsoBytes
The amount, in bytes, of isochronous data.
InterruptBytes
The amount, in bytes, of interrupt data.
ControlDataBytes
The amount, in bytes, of control data.
PciInterruptCount
The amount, in bytes, of interrupt data.
HardResetCount
The number of hard bus resets that have occurred.
WorkerSignalCount
The number of times that a worker thread has signaled completion of a task.
CommonBufferBytes
The number of bytes that are transferred by common buffer.
WorkerIdleTimeMs
The amount of time, in milliseconds, that worker threads have been idle.
RootHubEnabled
A Boolean value that indicates whether the root hub is enabled. If TRUE, he root hub is enabled. If FALSE, the root hub is disabled.
RootHubDevicePowerState
The power state of the root hub devices. This member can have any of the following values:
| Value | Meaning |
|---|---|
| 0 | D0 power state |
| 1 | D1 power state |
| 2 | D2 power state |
| 3 | D3 power state |
Unused
If this member is 1, the bus is active. If 0, the bus is inactive.
NameIndex
The index that is used to generate a symbolic link name for the hub PDO. This format of the symbolic link is USBPDO-n, where n is the value in NameIndex.
Remarks
The USB_BUS_STATISTICS_0 structure is used with the USBUSER_BUS_STATISTICS_0 user-mode request. For a description of this request, see IOCTL_USB_USER_REQUEST.
In Windows 8, this request completes successfully. However, the values retrieved from the underlying USB 3.0 driver stack do not reflect actual bus statistics.
Requirements
| Requirement | Value |
|---|---|
| Header | usbuser.h (include Usbuser.h) |