diff --git a/src/cryptoki.hxx b/src/cryptoki.hxx
index b0031ff..fd6a38c 100644
--- a/src/cryptoki.hxx
+++ b/src/cryptoki.hxx
@@ -830,6 +830,10 @@ namespace cryptoki {
 
       //@}
 
+      Library& library() {
+        return _library;
+      }
+
       MechanismInfo mechanisminfo(CK_MECHANISM_TYPE mechanism) {
         CRYPTOLOG("log");
         MechanismInfo info(mechanism);
@@ -962,7 +966,7 @@ namespace cryptoki {
 
       bool check(CK_RV result, const std::string& context="") {
         _res = result;
-        if (_slot._library.exc() && !*this) {
+        if (_slot.library().exc() && !*this) {
           if (!context.empty()) {
             throw access_error(context+": "+error());
           } else {
@@ -976,7 +980,7 @@ namespace cryptoki {
       void open(bool rw=false) {
         CRYPTOLOG("references: "<<slots().count(_slot._slot));
         if (slots().count(_slot._slot)==0) {
-          check(_slot._library->C_OpenSession
+          check(_slot.library()->C_OpenSession
                 (_slot._slot, CKF_SERIAL_SESSION|(rw?CKF_RW_SESSION:0),
                  0, 0, &_session),
                 CRYPTOKI_FN_LOG("C_OpenSession"));
@@ -991,7 +995,7 @@ namespace cryptoki {
         CRYPTOLOG("references: "<<slots().count(_slot._slot));
         if (slots().count(_slot._slot)==1) {
           slots().erase(slots().find(_slot._slot));
-          check(_slot._library->C_CloseSession(_session),
+          check(_slot.library()->C_CloseSession(_session),
                 CRYPTOKI_FN_LOG("C_CloseSession"));
         } else {
           slots().erase(slots().find(_slot._slot));
@@ -1078,7 +1082,7 @@ namespace cryptoki {
 
       /*! @return error text of last cryptoki call */
       std::string error() {
-        return _slot._library.error(_res);
+        return _slot.library().error(_res);
       }
 
       //@}
@@ -1092,7 +1096,7 @@ namespace cryptoki {
       bool cancel() {
         CRYPTOLOG("log");
         //! calls @c C_CancelFunction
-        return check(_slot._library->C_CancelFunction(_session),
+        return check(_slot.library()->C_CancelFunction(_session),
                      CRYPTOKI_FN_LOG("C_CancelFunction"));
       }
 
@@ -1105,7 +1109,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_Digest
-        check(_slot._library->C_Digest
+        check(_slot.library()->C_Digest
               (_session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1120,7 +1124,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_DigestEncryptUpdate
-        check(_slot._library->C_DigestEncryptUpdate
+        check(_slot.library()->C_DigestEncryptUpdate
               (_session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1134,7 +1138,7 @@ namespace cryptoki {
       bool digestfinal() {
           CRYPTOLOG("log");
         //! calls @c C_DigestFinal
-        return check(_slot._library->C_DigestFinal(_session, CK_BYTE_PTR, CK_ULONG_PTR),
+        return check(_slot.library()->C_DigestFinal(_session, CK_BYTE_PTR, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_DigestFinal"));
       }
           @endcode */
@@ -1144,7 +1148,7 @@ namespace cryptoki {
       bool digestinit() {
           CRYPTOLOG("log");
         //! calls @c C_DigestInit
-        return check(_slot._library->C_DigestInit(_session, CK_MECHANISM_PTR),
+        return check(_slot.library()->C_DigestInit(_session, CK_MECHANISM_PTR),
                      CRYPTOKI_FN_LOG("C_DigestInit"));
       }
           @endcode */
@@ -1154,7 +1158,7 @@ namespace cryptoki {
       bool digestupdate() {
           CRYPTOLOG("log");
         //! calls @c C_DigestUpdate
-        return check(_slot._library->C_DigestUpdate(_session, CK_BYTE_PTR, CK_ULONG),
+        return check(_slot.library()->C_DigestUpdate(_session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_DigestUpdate"));
       }
           @endcode */
@@ -1164,7 +1168,7 @@ namespace cryptoki {
       bool findobjectsfinal() {
           CRYPTOLOG("log");
         //! calls @c C_FindObjectsFinal
-        return check(_slot._library->C_FindObjectsFinal(_session),
+        return check(_slot.library()->C_FindObjectsFinal(_session),
                      CRYPTOKI_FN_LOG("C_FindObjectsFinal"));
       }
           @endcode */
@@ -1174,7 +1178,7 @@ namespace cryptoki {
       bool findobjectsinit() {
           CRYPTOLOG("log");
         //! calls @c C_FindObjectsInit
-        return check(_slot._library->C_FindObjectsInit(_session, CK_ATTRIBUTE_PTR, CK_ULONG),
+        return check(_slot.library()->C_FindObjectsInit(_session, CK_ATTRIBUTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_FindObjectsInit"));
       }
           @endcode */
@@ -1184,7 +1188,7 @@ namespace cryptoki {
       bool findobjects() {
           CRYPTOLOG("log");
         //! calls @c C_FindObjects
-        return check(_session->_slot._library->C_FindObjects(_session, CK_OBJECT_HANDLE_PTR, CK_ULONG,
+        return check(_session->_slot.library()->C_FindObjects(_session, CK_OBJECT_HANDLE_PTR, CK_ULONG,
                                    CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_FindObjects"));
       }
@@ -1195,7 +1199,7 @@ namespace cryptoki {
       bool generaterandom() {
           CRYPTOLOG("log");
         //! calls @c C_GenerateRandom
-        return check(_slot._library->C_GenerateRandom(_session, CK_BYTE_PTR, CK_ULONG),
+        return check(_slot.library()->C_GenerateRandom(_session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_GenerateRandom"));
       }
           @endcode */
@@ -1205,7 +1209,7 @@ namespace cryptoki {
       bool getfunctionstatus() {
           CRYPTOLOG("log");
         //! calls @c C_GetFunctionStatus
-        return check(_slot._library->C_GetFunctionStatus(_session),
+        return check(_slot.library()->C_GetFunctionStatus(_session),
                      CRYPTOKI_FN_LOG("C_GetFunctionStatus"));
       }
           @endcode */
@@ -1215,7 +1219,7 @@ namespace cryptoki {
       bool getoperationstate() {
           CRYPTOLOG("log");
         //! calls @c C_GetOperationState
-        return check(_slot._library->C_GetOperationState(_session, CK_BYTE_PTR, CK_ULONG_PTR),
+        return check(_slot.library()->C_GetOperationState(_session, CK_BYTE_PTR, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_GetOperationState"));
       }
           @endcode */
@@ -1255,7 +1259,7 @@ namespace cryptoki {
         CRYPTOLOG("log");
         CK_SESSION_INFO info;
         //! calls @c C_GetSessionInfo
-        check(_slot._library->C_GetSessionInfo(_session, &info),
+        check(_slot.library()->C_GetSessionInfo(_session, &info),
               CRYPTOKI_FN_LOG("C_GetSessionInfo"));
         return info;
       }
@@ -1276,7 +1280,7 @@ namespace cryptoki {
       bool initpin() {
           CRYPTOLOG("log");
         //! calls @c C_InitPIN
-        return check(_slot._library->C_InitPIN(_session, CK_CHAR_PTR, CK_ULONG),
+        return check(_slot.library()->C_InitPIN(_session, CK_CHAR_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_InitPIN"));
       }
           @endcode */
@@ -1292,7 +1296,7 @@ namespace cryptoki {
                 CK_USER_TYPE userType=CKU_USER): _session(session) {
             CRYPTOLOG("log");
             //! calls @c C_Login
-            _session.check(_session._slot._library->C_Login
+            _session.check(_session._slot.library()->C_Login
                             (_session._session, userType,
                              (CK_CHAR*)pin.c_str(),
                              pin.size()),
@@ -1302,7 +1306,7 @@ namespace cryptoki {
           ~Login() {
             try {
               //! calls @c C_Logout
-              _session.check(_session._slot._library->C_Logout
+              _session.check(_session._slot.library()->C_Logout
                              (_session._session),
                              CRYPTOKI_FN_LOG("C_Logout"));
             } catch (const std::exception& x) {
@@ -1339,7 +1343,7 @@ namespace cryptoki {
       bool seedrandom() {
           CRYPTOLOG("log");
         //! calls @c C_SeedRandom
-        return check(_slot._library->C_SeedRandom(_session, CK_BYTE_PTR, CK_ULONG),
+        return check(_slot.library()->C_SeedRandom(_session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_SeedRandom"));
       }
           @endcode */
@@ -1349,7 +1353,7 @@ namespace cryptoki {
       bool setpin() {
           CRYPTOLOG("log");
         //! calls @c C_SetPIN
-        return check(_slot._library->C_SetPIN(_session, CK_CHAR_PTR, CK_ULONG, CK_CHAR_PTR, CK_ULONG),
+        return check(_slot.library()->C_SetPIN(_session, CK_CHAR_PTR, CK_ULONG, CK_CHAR_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_SetPIN"));
       }
           @endcode */
@@ -1367,7 +1371,7 @@ namespace cryptoki {
 
       bool check(CK_RV result, const std::string& context="") {
         _res = result;
-        if (_session._slot._library.exc() && !*this) {
+        if (_session._slot.library().exc() && !*this) {
           if (!context.empty()) {
             throw access_error(context+": "+error());
           } else {
@@ -1450,7 +1454,7 @@ namespace cryptoki {
 
       /*! @return error text of last cryptoki call */
       std::string error() {
-        return _session._slot._library.error(_res);
+        return _session._slot.library().error(_res);
       }      
 
       //@}
@@ -1466,7 +1470,7 @@ namespace cryptoki {
       bool copyobject() {
           CRYPTOLOG("log");
         //! calls @c C_CopyObject
-        return check(_session._slot._library->C_CopyObject(_session._session, CK_OBJECT_HANDLE,
+        return check(_session._slot.library()->C_CopyObject(_session._session, CK_OBJECT_HANDLE,
                                   CK_ATTRIBUTE_PTR, CK_ULONG, CK_OBJECT_HANDLE_PTR),
                      CRYPTOKI_FN_LOG("C_CopyObject"));
       }
@@ -1480,7 +1484,7 @@ namespace cryptoki {
         CRYPTOLOG("decryptinit: type="<<type<<"; mech=("<<mech.mechanism
                      <<", "<<mech.pParameter<<", "<<mech.ulParameterLen<<')');
         //! calls @c C_DecryptInit
-        return check(_session._slot._library->C_DecryptInit
+        return check(_session._slot.library()->C_DecryptInit
                      (_session._session, &mech, _object),
                      CRYPTOKI_FN_LOG("C_DecryptInit"));
       }
@@ -1492,13 +1496,13 @@ namespace cryptoki {
         CK_ULONG size(0); // two calls, first to get minimum buffer length
         CRYPTOLOG("get size");
         //! calls @c C_Decrypt
-        check(_session._slot._library->C_Decrypt
+        check(_session._slot.library()->C_Decrypt
               (_session._session,
                (unsigned char*)&in[0], in.size(), 0, &size),
               CRYPTOKI_FN_LOG("C_Decrypt"));
         CRYPTOLOG("maximum size is "<<size<<"Bytes");
         res.resize(size, 0);
-        check(_session._slot._library->C_Decrypt
+        check(_session._slot.library()->C_Decrypt
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1514,7 +1518,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_DecryptDigestUpdate
-        check(_session._slot._library->C_DecryptDigestUpdate
+        check(_session._slot.library()->C_DecryptDigestUpdate
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1526,7 +1530,7 @@ namespace cryptoki {
       bool decryptfinal() {
         CRYPTOLOG("log");
         //! calls @c C_DecryptFinal
-        return check(_session._slot._library->C_DecryptFinal
+        return check(_session._slot.library()->C_DecryptFinal
                      (_session._session, 0, 0),
               CRYPTOKI_FN_LOG("C_DecryptFinal"));
         //! @todo does this work?
@@ -1538,7 +1542,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_DecryptUpdate
-        check(_session._slot._library->C_DecryptUpdate
+        check(_session._slot.library()->C_DecryptUpdate
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1553,7 +1557,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_DecryptVerifyUpdate
-        check(_session._slot._library->C_DecryptVerifyUpdate
+        check(_session._slot.library()->C_DecryptVerifyUpdate
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1567,14 +1571,14 @@ namespace cryptoki {
         CRYPTOLOG("log");
         std::string res;
         CK_ULONG size(0);
-        check(_session._slot._library->C_Sign
+        check(_session._slot.library()->C_Sign
               (_session._session,
                (unsigned char*)&in[0], in.size(),0, &size),
               CRYPTOKI_FN_LOG("C_Sign"));
         CRYPTOLOG("maximum size is "<<size<<"Bytes");
         res.resize(size, 0);
         //! calls @c C_Sign
-        check(_session._slot._library->C_Sign
+        check(_session._slot.library()->C_Sign
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1590,7 +1594,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_SignEncryptUpdate
-        check(_session._slot._library->C_SignEncryptUpdate
+        check(_session._slot.library()->C_SignEncryptUpdate
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1604,7 +1608,7 @@ namespace cryptoki {
       bool signfinal() {
           CRYPTOLOG("log");
         //! calls @c C_SignFinal
-        return check(_slot._library->C_SignFinal(_session, CK_BYTE_PTR, CK_ULONG_PTR),
+        return check(_slot.library()->C_SignFinal(_session, CK_BYTE_PTR, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_SignFinal"));
       }
           @endcode */
@@ -1615,7 +1619,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_SignRecover
-        check(_session._slot._library->C_SignRecover
+        check(_session._slot.library()->C_SignRecover
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1629,7 +1633,7 @@ namespace cryptoki {
       bool signupdate() {
           CRYPTOLOG("log");
         //! calls @c C_SignUpdate
-        return check(_session._slot._library->C_SignUpdate(_session._session, CK_BYTE_PTR, CK_ULONG),
+        return check(_session._slot.library()->C_SignUpdate(_session._session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_SignUpdate"));
       }
           @endcode */
@@ -1637,7 +1641,7 @@ namespace cryptoki {
       bool verify(std::string data, std::string signature) {
         CRYPTOLOG("log");
         //! calls @c C_Verify
-        return check(_session._slot._library->C_Verify
+        return check(_session._slot.library()->C_Verify
                      (_session._session,
                       (unsigned char*)&data[0], data.size(),
                       (unsigned char*)&signature[0], signature.size()),
@@ -1649,7 +1653,7 @@ namespace cryptoki {
       bool verifyfinal() {
           CRYPTOLOG("log");
         //! calls @c C_VerifyFinal
-        return check(_session._slot._library->C_VerifyFinal(_session._session, CK_BYTE_PTR, CK_ULONG),
+        return check(_session._slot.library()->C_VerifyFinal(_session._session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_VerifyFinal"));
       }
           @endcode */
@@ -1660,7 +1664,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_VerifyRecover
-        check(_session._slot._library->C_VerifyRecover
+        check(_session._slot.library()->C_VerifyRecover
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1674,7 +1678,7 @@ namespace cryptoki {
       bool verifyupdate() {
           CRYPTOLOG("log");
         //! calls @c C_VerifyUpdate
-        return check(_session._slot._library->C_VerifyUpdate(_session._session, CK_BYTE_PTR, CK_ULONG),
+        return check(_session._slot.library()->C_VerifyUpdate(_session._session, CK_BYTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_VerifyUpdate"));
       }
           @endcode */
@@ -1685,7 +1689,7 @@ namespace cryptoki {
       bool derivekey() {
           CRYPTOLOG("log");
         //! calls @c C_DeriveKey
-        return check(_session._slot._library->C_DeriveKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
+        return check(_session._slot.library()->C_DeriveKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
                                  CK_ATTRIBUTE_PTR, CK_ULONG, CK_OBJECT_HANDLE_PTR),
                      CRYPTOKI_FN_LOG("C_DeriveKey"));
       }
@@ -1694,7 +1698,7 @@ namespace cryptoki {
       bool destroy() {
         CRYPTOLOG("log");
         //! calls @c C_DestroyObject
-        return check(_session._slot._library->C_DestroyObject
+        return check(_session._slot.library()->C_DestroyObject
                      (_session._session, _object),
                      CRYPTOKI_FN_LOG("C_DestroyObject"));
       }
@@ -1705,7 +1709,7 @@ namespace cryptoki {
       bool digestkey() {
           CRYPTOLOG("log");
         //! calls @c C_DigestKey
-        return check(_session._slot._library->C_DigestKey(_session._session, CK_OBJECT_HANDLE),
+        return check(_session._slot.library()->C_DigestKey(_session._session, CK_OBJECT_HANDLE),
                      CRYPTOKI_FN_LOG("C_DigestKey"));
       }
           @endcode */
@@ -1718,7 +1722,7 @@ namespace cryptoki {
         CRYPTOLOG("encryptinit: type="<<type<<"; mech=("<<mech.mechanism
                      <<", "<<mech.pParameter<<", "<<mech.ulParameterLen<<')');
         //! calls @c C_EncryptInit
-        return check(_session._slot._library->C_EncryptInit
+        return check(_session._slot.library()->C_EncryptInit
                      (_session._session, &mech, _object),
                      CRYPTOKI_FN_LOG("C_EncryptInit"));
       }
@@ -1729,13 +1733,13 @@ namespace cryptoki {
         CK_ULONG size(0); // two calls, first to get minimum buffer length
         CRYPTOLOG("get size");
         //! calls @c C_Encrypt
-        check(_session._slot._library->C_Encrypt
+        check(_session._slot.library()->C_Encrypt
               (_session._session,
                (unsigned char*)&in[0], in.size(), 0, &size),
               CRYPTOKI_FN_LOG("C_Decrypt"));
         CRYPTOLOG("maximum size is "<<size<<"Bytes");
         res.resize(size, 0);
-        check(_session._slot._library->C_Encrypt
+        check(_session._slot.library()->C_Encrypt
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1749,7 +1753,7 @@ namespace cryptoki {
       bool encryptfinal() {
           CRYPTOLOG("log");
         //! calls @c C_EncryptFinal
-        return check(_session._slot._library->C_EncryptFinal(_session._session, CK_BYTE_PTR, CK_ULONG_PTR),
+        return check(_session._slot.library()->C_EncryptFinal(_session._session, CK_BYTE_PTR, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_EncryptFinal"));
       }
           @endcode */
@@ -1760,7 +1764,7 @@ namespace cryptoki {
         res.resize(in.size());
         CK_ULONG size(res.size()); //! @todo check if size is ok
         //! calls @c C_EncryptUpdate
-        check(_session._slot._library->C_EncryptUpdate
+        check(_session._slot.library()->C_EncryptUpdate
               (_session._session,
                (unsigned char*)&in[0], in.size(),
                (unsigned char*)&res[0], &size),
@@ -1774,7 +1778,7 @@ namespace cryptoki {
       bool generatekey() {
           CRYPTOLOG("log");
         //! calls @c C_GenerateKey
-        return check(_session._slot._library->C_GenerateKey(_session._session, CK_MECHANISM_PTR, CK_ATTRIBUTE_PTR,
+        return check(_session._slot.library()->C_GenerateKey(_session._session, CK_MECHANISM_PTR, CK_ATTRIBUTE_PTR,
                                    CK_ULONG, CK_OBJECT_HANDLE_PTR),
                      CRYPTOKI_FN_LOG("C_GenerateKey"));
       }
@@ -1786,7 +1790,7 @@ namespace cryptoki {
       bool generatekeypair() {
           CRYPTOLOG("log");
         //! calls @c C_GenerateKeyPair
-        return check(_session._slot._library->C_GenerateKeyPair(_session._session, CK_MECHANISM_PTR, CK_ATTRIBUTE_PTR,
+        return check(_session._slot.library()->C_GenerateKeyPair(_session._session, CK_MECHANISM_PTR, CK_ATTRIBUTE_PTR,
                                        CK_ULONG, CK_ATTRIBUTE_PTR, CK_ULONG,
                                        CK_OBJECT_HANDLE_PTR, CK_OBJECT_HANDLE_PTR),
                      CRYPTOKI_FN_LOG("C_GenerateKeyPair"));
@@ -1806,7 +1810,7 @@ namespace cryptoki {
         Attribute res;
         CK_ATTRIBUTE attr((CK_ATTRIBUTE){a, 0, 0});
         //! calls @c C_GetAttributeValue
-        if (!check(_session._slot._library->C_GetAttributeValue
+        if (!check(_session._slot.library()->C_GetAttributeValue
                    (_session._session, _object, &attr, 1),
                    CRYPTOKI_FN_LOG("C_GetAttributeValue"))
             || !(long)attr.ulValueLen>0l)
@@ -1815,7 +1819,7 @@ namespace cryptoki {
         try {
           attr.pValue = malloc(attr.ulValueLen);
           attr.pValue = memset(attr.pValue, 0, attr.ulValueLen);
-          if (check(_session._slot._library->C_GetAttributeValue
+          if (check(_session._slot.library()->C_GetAttributeValue
                     (_session._session, _object, &attr, 1),
                     CRYPTOKI_FN_LOG("C_GetAttributeValue")))
             /*! @todo There's no @c CKA_WRAP_TEMPLATE in Open
@@ -1931,7 +1935,7 @@ namespace cryptoki {
           attr = (CK_ATTRIBUTE){*it, 0, 0};
           try {
             //! calls @c C_GetAttributeValue
-            if (_session._slot._library->C_GetAttributeValue
+            if (_session._slot.library()->C_GetAttributeValue
                 (_session._session, _object, &attr, 1)
                 == CKR_ATTRIBUTE_TYPE_INVALID
                 || _res == CKR_ATTRIBUTE_SENSITIVE) {
@@ -1941,7 +1945,7 @@ namespace cryptoki {
               if ((long)attr.ulValueLen>0l) {
                 attr.pValue = malloc(attr.ulValueLen);
                 attr.pValue = memset(attr.pValue, 0, attr.ulValueLen);
-                if (check(_session._slot._library->C_GetAttributeValue
+                if (check(_session._slot.library()->C_GetAttributeValue
                           (_session._session, _object, &attr, 1),
                           CRYPTOKI_FN_LOG("C_GetAttributeValue")))
                   /*! @todo There's no @c CKA_WRAP_TEMPLATE in Open
@@ -2003,7 +2007,7 @@ namespace cryptoki {
       bool getobjectsize() {
           CRYPTOLOG("log");
         //! calls @c C_GetObjectSize
-        return check(_session._slot._library->C_GetObjectSize(_session._session, CK_OBJECT_HANDLE, CK_ULONG_PTR),
+        return check(_session._slot.library()->C_GetObjectSize(_session._session, CK_OBJECT_HANDLE, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_GetObjectSize"));
       }
           @endcode */
@@ -2014,7 +2018,7 @@ namespace cryptoki {
       bool setattributevalue() {
           CRYPTOLOG("log");
         //! calls @c C_SetAttributeValue
-        return check(_session._slot._library->C_SetAttributeValue(_session._session, CK_OBJECT_HANDLE,
+        return check(_session._slot.library()->C_SetAttributeValue(_session._session, CK_OBJECT_HANDLE,
                                          CK_ATTRIBUTE_PTR, CK_ULONG),
                      CRYPTOKI_FN_LOG("C_SetAttributeValue"));
       }
@@ -2025,7 +2029,7 @@ namespace cryptoki {
       bool setoperationstate() {
           CRYPTOLOG("log");
         //! calls @c C_SetOperationState
-        return check(_session._slot._library->C_SetOperationState(_session._session, CK_BYTE_PTR, CK_ULONG,
+        return check(_session._slot.library()->C_SetOperationState(_session._session, CK_BYTE_PTR, CK_ULONG,
                                          CK_OBJECT_HANDLE, CK_OBJECT_HANDLE),
                      CRYPTOKI_FN_LOG("C_SetOperationState"));
       }
@@ -2039,7 +2043,7 @@ namespace cryptoki {
         CRYPTOLOG("signinit: type="<<type<<"; mech=("<<mech.mechanism
                      <<", "<<mech.pParameter<<", "<<mech.ulParameterLen<<')');
         //! calls @c C_SignInit
-        return check(_session._slot._library->C_SignInit
+        return check(_session._slot.library()->C_SignInit
                      (_session._session, &mech, _object),
                      CRYPTOKI_FN_LOG("C_SignInit"));
       }
@@ -2049,7 +2053,7 @@ namespace cryptoki {
       bool signrecoverinit() {
           CRYPTOLOG("log");
         //! calls @c C_SignRecoverInit
-        return check(_session._slot._library->C_SignRecoverInit(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE),
+        return check(_session._slot.library()->C_SignRecoverInit(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE),
                      CRYPTOKI_FN_LOG("C_SignRecoverInit"));
       }
           @endcode */
@@ -2059,7 +2063,7 @@ namespace cryptoki {
       bool unwrapkey() {
           CRYPTOLOG("log");
         //! calls @c C_UnwrapKey
-        return check(_session._slot._library->C_UnwrapKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
+        return check(_session._slot.library()->C_UnwrapKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
                                  CK_BYTE_PTR, CK_ULONG, CK_ATTRIBUTE_PTR, CK_ULONG,
                                  CK_OBJECT_HANDLE_PTR),
                      CRYPTOKI_FN_LOG("C_UnwrapKey"));
@@ -2074,7 +2078,7 @@ namespace cryptoki {
         CRYPTOLOG("verifyinit: type="<<type<<"; mech=("<<mech.mechanism
                      <<", "<<mech.pParameter<<", "<<mech.ulParameterLen<<')');
          //! calls @c C_VerifyInit
-        return check(_session._slot._library->C_VerifyInit
+        return check(_session._slot.library()->C_VerifyInit
                      (_session._session, &mech, _object),
                      CRYPTOKI_FN_LOG("C_VerifyInit"));
       }
@@ -2084,7 +2088,7 @@ namespace cryptoki {
       bool verifyrecoverinit() {
           CRYPTOLOG("log");
         //! calls @c C_VerifyRecoverInit
-        return check(_session._slot._library->C_VerifyRecoverInit(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE),
+        return check(_session._slot.library()->C_VerifyRecoverInit(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE),
                      CRYPTOKI_FN_LOG("C_VerifyRecoverInit"));
       }
           @endcode */
@@ -2095,7 +2099,7 @@ namespace cryptoki {
       bool wrapkey() {
           CRYPTOLOG("log");
         //! calls @c C_WrapKey
-        return check(_session._slot._library->C_WrapKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
+        return check(_session._slot.library()->C_WrapKey(_session._session, CK_MECHANISM_PTR, CK_OBJECT_HANDLE,
                                CK_OBJECT_HANDLE, CK_BYTE_PTR, CK_ULONG_PTR),
                      CRYPTOKI_FN_LOG("C_WrapKey"));
       }
diff --git a/src/openssl-engine.hxx b/src/openssl-engine.hxx
index 2eafa7e..0f1f9fa 100644
--- a/src/openssl-engine.hxx
+++ b/src/openssl-engine.hxx
@@ -32,9 +32,9 @@
 #if __GNUC__ >= 2
 //! Macro for internal OpenSSL checks.
 /*! You can define a different implementation in your compile call */
-#define OPENSSL_CHECK(X) if (!X) {ERR_load_ENGINE_strings(); std::stringstream ss; for (unsigned int err(0); err=ERR_get_error();) ss<<"Error: "<<ERR_error_string(err, 0)<<"; "; ss<<"Command "<<#X<<" failed in function "<<__PRETTY_FUNCTION__<<" in file "<<__FILE__<<":"<<__LINE__; throw std::runtime_error(ss.str());}
+#define OPENSSL_CHECK(X) if (!(X)) {ERR_load_ENGINE_strings(); std::stringstream ss; for (unsigned int err(0); err=ERR_get_error();) ss<<"Error: "<<ERR_error_string(err, 0)<<"; "; ss<<"Command "<<#X<<" failed in function "<<__PRETTY_FUNCTION__<<" in file "<<__FILE__<<":"<<__LINE__; throw std::runtime_error(ss.str());}
 #else
-#define OPENSSL_CHECK(X) if (!X) {ERR_load_ENGINE_strings(); std::stringstream ss; for (unsigned int err(0); err=ERR_get_error();) ss<<"Error: "<<ERR_error_string(err, 0)<<"; "; ss<<"Command "<<#X<<" failed in file "<<__FILE__<<":"<<__LINE__; throw std::runtime_error(ss.str());}
+#define OPENSSL_CHECK(X) if (!(X)) {ERR_load_ENGINE_strings(); std::stringstream ss; for (unsigned int err(0); err=ERR_get_error();) ss<<"Error: "<<ERR_error_string(err, 0)<<"; "; ss<<"Command "<<#X<<" failed in file "<<__FILE__<<":"<<__LINE__; throw std::runtime_error(ss.str());}
 #endif
 #endif