The BluetoothGATTGetServices function gets all the primary services available for a server.
HRESULT BluetoothGATTGetServices( HANDLE hDevice, USHORT ServicesBufferCount, PBTH_LE_GATT_SERVICE ServicesBuffer, USHORT *ServicesBufferActual, ULONG Flags );
Handle to the Bluetooth device from which to obtain the list of primary services.
The number of elements allocated for the ServicesBuffer parameter.
Pointer to buffer containing a BTH_LE_GATT_SERVICE structure into which to return services.
Pointer to buffer into which the actual number of services were returned in the ServicesBuffer parameter.
Flags to modify the behavior of BluetoothGATTGetServices:
|BLUETOOTH_GATT_FLAG_NONE||The client does not have specific GATT requirements (default).|
This function returns the following values:
||The operation completed successfully.|
||The buffer parameter is NULL and the number of items available is being returned instead.|
||Returned if both a parent service and a service handle are provided and the service hierarchy does not roll up to the provided parent service handle.|
One of the following conditions occurred:
||A buffer is specified, but the buffer count size is smaller than what is required, in bytes.|
||Services were specified to be retrieved from the cache, but no services are present in the cache.|
||The current data in the cache appears to be inconsistent, and is leading to internal errors.|
||The operation ran out of memory.|
Returned services are cached upon successful retrieval of services from the device directly. Unless a service-change event is received, the list of returned services is not expected to change.
Profile drivers should pre-allocate a sufficiently large buffer for the array of primary services to be returned in. Callers can determine the necessary buffer size by passing a non-NULL value in ServicesBufferActual and NULL in ServicesBuffer.
Do not modify the returned service structure, and then use the modified structure in subsequent function calls. Behavior is undefined if the caller does this.
//////////////////////////////////////////////////////////////////////////// // Determine Services Buffer Size ////////////////////////////////////////////////////////////////////////////
|Minimum supported client||Supported in Windows 8 and later versions of Windows.|