SCardIsValidContext function (winscard.h)

The SCardIsValidContext function determines whether a smart card context handle is valid.

Syntax

LONG SCardIsValidContext(
 [in] SCARDCONTEXT hContext
);

Parameters

[in] hContext

Handle that identifies the resource manager context. The resource manager context can be set by a previous call to SCardEstablishContext.

Return value

This function returns one of the following values.

Remarks

Call this function to determine whether a smart card context handle is still valid. After a smart card context handle has been set by SCardEstablishContext, it may become not valid if the resource manager service has been shut down.

Examples

The following example shows determining whether a smart card context handle is valid.

// Check the smart card context handle.
// hContext was set previously by SCardEstablishContext.

LONG lReturn;
lReturn = SCardIsValidContext(hContext);
if ( SCARD_S_SUCCESS != lReturn )
{
 // Function failed; check return value.
 if ( ERROR_INVALID_HANDLE == lReturn )
 printf("Handle is invalid\n");
 else
 {
 // Some unexpected error occurred; report and bail out.
 printf("Failed SCardIsValidContext - %x\n", lReturn);
 exit(1); // Or other appropriate error action.
 }
}
else
{
 // Handle is valid; proceed as needed.
 // ...
}

Requirements

See also

SCardEstablishContext