The SCardStatus function provides the current status of a smart card in a reader. You can call it any time after a successful call to SCardConnect and before a successful call to SCardDisconnect. It does not affect the state of the reader or reader driver.

The SCardConnect function establishes a connection (using a specific resource manager context) between the calling application and a smart card contained by a specific reader. If no card exists in the specified reader, an error is returned.

The SCardDisconnect function terminates a connection previously opened between the calling application and a smart card in the target reader.