IOCTL_BTHX_QUERY_CAPABILITIES IOCTL (bthxddi.h)
IOCTL_BTHX_QUERY_CAPABILITIES is used to query the capabilities of the transport driver.
Major code
Input buffer
None.
Input buffer length
None.
Output buffer
The AssociatedIrp.SystemBuffer member points to a buffer that holds a BTHX_CAPABILITIES structure.
Output buffer length
The length of the buffer is the size of the BTHX_CAPABILITIES structure.
Status block
The Information member of the STATUS_BLOCK structure is set to the size of the structure.
The Status member is set to one of the values in the following table.
| Status value | Description |
|---|---|
| STATUS_SUCCESS | The IOCTL completed successfully. |
Remarks
During startup, the Bluetooth stack sends IOCTL_BTHX_QUERY_CAPABILITIES to query the capabilities of the transport driver.
This is a synchronous call and failure of this IOCTL prevents Windows from loading the Bluetooth stack.
The output buffer of this IOCTL is defined by the BTHX_CAPABILITIES structure.
The MaxScoChannels member must be set to 1. The ScoSupport member must be set to ScoSupportHCIBypass. Failure to do so prevents the stack from being loaded.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Supported starting with Windows 8. |
| Header | bthxddi.h |
| IRQL | <= DISPATCH_LEVEL |