(require mzlib/foreign) 
(unsafe!)


  (define winscard (ffi-lib "winscard"))
  
  (define _DWORD _int)
  (define _LONG _int)
  (define _SCARDHANDLE _int) ;; AN OPAQUE POINTER WOULD BE BETTER.
  
  (define 	+SCARD_PROTOCOL_T0+   #x0001) ;; T=0 active protocol.
  (define 	+SCARD_PROTOCOL_T1+   #x0002) ;; T=1 active protocol.
  (define 	+SCARD_PROTOCOL_ANY+   (bitwise-ior +SCARD_PROTOCOL_T0+ +SCARD_PROTOCOL_T1+))
  
  
  (define-cstruct _SCARD_IO_REQUEST ((dwProtocol _DWORD)
                                     (cbPciLength _DWORD)))
  
  (define +sizeof-SCARD_IO_REQUEST+ (+ (ctype-sizeof _DWORD) 
                                       (ctype-sizeof _DWORD))) ;; Any way to have it generated automatically?
  
  
#|
LONG SCardTransmit(
    IN     SCARDHANDLE hCard,
    IN     LPCSCARD_IO_REQUEST pioSendPci,
    IN     LPCBYTE pbSendBuffer,
    IN     DWORD cbSendLength,
    IN OUT LPSCARD_IO_REQUEST pioRecvPci, // It can be NULL.
    OUT    LPBYTE pbRecvBuffer,
    IN OUT LPDWORD pcbRecvLength);
|#
  (define SCardTransmit
    (get-ffi-obj "SCardTransmit"
                 winscard
                 (_fun (hCard : _SCARDHANDLE) ;; == IN SCARDHANDLE hCard
                       (pioSendPci : (_ptr i _SCARD_IO_REQUEST)) ;; == IN LPCSCARD_IO_REQUEST pioSendPci
                       (pbSendBuffer : (_vector i _byte)) ;; == IN LPCBYTE pbSendBuffer
                       (_DWORD = (vector-length pbSendBuffer)) ;; == IN DWORD cbSendLength
                       (ioRecvPci : (_ptr io _SCARD_IO_REQUEST-pointer/null)) ;; == IN OUT LPSCARD_IO_REQUEST pioRecvPci
                       (pbRecvBuffer :  (_vector o _byte cbRecvLength)) ;; == OUT LPBYTE pbRecvBuffer
                       (cbRecvLength : (_ptr io _DWORD)) ;; == IN OUT LPDWORD pcbRecvLength
                       -> (error : _LONG) 
                       )))
  
  


(SCardTransmit 1 
                (make-SCARD_IO_REQUEST +SCARD_PROTOCOL_ANY+ +sizeof-SCARD_IO_REQUEST+)
                (make-vector 4 0) 
                ;; cbSendLength AUTOMATICALLY GENERATED.
                #f ;; PASSING NULL.
                ;; pbRecvBuffer SKIPPED SENCE IS AN OUTPUT PARAMETER.
                4
                )