The IOCTL_SMARTCARD_IS_PRESENT DeviceIoControl operation either returns immediately if no card is currently inserted, or it installs an event handler to track card insertions.
The operation either returns immediately with STATUS_SUCCESS, which indicates that a card is already in the reader, or it returns with STATUS_PENDING, which indicates that no card is currently in the reader. In this case, the driver then informs the caller of card insertion through an I/O completion. Waiting for I/O completion can be accomplished with the following code fragment:
success = GetOverlappedResult(
hDevice,
&lpOverlapped,
&lpBytesReturned,
TRUE);
Information must be set to zero. Status can be:
Status | Meaning |
---|---|
STATUS_SUCCESS | No smart card is currently inserted. |
STATUS_PENDING | The driver is waiting for a card to be removed. |
STATUS_DEVICE_BUSY | Event tracking is already active. |
STATUS_INVALID_DEVICE_STATE | The device cannot accept the request. |
The IOCTL_SMARTCARD_IS_PRESENT DeviceIoControl operation either returns immediately if no card is currently inserted, or it installs an event handler to track card insertions.
The operation either returns immediately with STATUS_SUCCESS, which indicates that a card is already in the reader, or it returns with STATUS_PENDING, which indicates that no card is currently in the reader. In this case, the driver then informs the caller of card insertion through an I/O completion. Waiting for I/O completion can be accomplished with the following code fragment:
success = GetOverlappedResult(
hDevice,
&lpOverlapped,
&lpBytesReturned,
TRUE);
Completing the call in the driver can be accomplished with the following code fragment:
SmartcardCompleteCardTracking(
SmartcardExtension
);
Following are possible return values.
Value | Meaning |
---|---|
STATUS_SUCCESS | No smart card is currently inserted. |
STATUS_PENDING | The driver is waiting for a card to be removed. |
STATUS_DEVICE_BUSY | Event tracking is already active. |
STATUS_INVALID_DEVICE_STATE | The device cannot accept the request. |