added method control; refs #18

src/pcsc.hxx

@@ -325,6 +325,24 @@ namespace pcsc {
             return std::string((char*)buff, len);
           }
 
+          //! Transmit control command and data to the reader.
+          /*!
+              * @note Take care: Strings may contain embedded @c 0.
+              */
+          std::string control(unsigned long controlCode,
+                              std::string in) {
+            DWORD len(256); // arbitrary
+            UCHAR dataBuffer[256];
+            PCSC_LOG("SCardControl: "<<"Command: "<<controlCode);
+            PCSC_LOG(" -> "<<crypto::hex(in));
+            check(SCardControl(_id, controlCode,
+                               (unsigned char*)in.c_str(), in.size(),
+                               dataBuffer, sizeof(dataBuffer), &len),
+                  "smartcard control message sent");
+            PCSC_LOG(" -> "<<crypto::hex(std::string((char*)dataBuffer, len)));
+            return std::string((char*)dataBuffer, len);
+          }
+          
           //! @c false if last operation was not successful
           operator bool() const {
             //  Values are 32 bit values layed out as follows: