Hi, all Compile error is occurred in the following program "VerySimpleCase .cpp" on http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/tutorial.html#si.... The statements in line no. 45 and 56 cause problems. Could you fix it up? Thanks, --Kim ps 1) VerySimpleCase .cpp 1 #include <fstream> 2 3 // include headers that implement a archive in simple text format 4 #include <boost/archive/text_oarchive.hpp> 5 #include <boost/archive/text_iarchive.hpp> 6 7 ///////////////////////////////////////////////////////////// 8 // gps coordinate 9 // 10 // illustrates serialization for a simple type 11 // 12 class gps_position 13 { 14 private: 15 friend class boost::serialization::access; 16 // When the class Archive corresponds to an output archive, the 17 // & operator is defined similar to <<. Likewise, when the class Archive 18 // is a type of input archive the & operator is defined similar to >>. 19 template<class Archive> 20 void serialize(Archive & ar, const unsigned int version) 21 { 22 ar & degrees; 23 ar & minutes; 24 ar & seconds; 25 } 26 int degrees; 27 int minutes; 28 float seconds; 29 public: 30 gps_position(){}; 31 gps_position(int d, int m, float s) : 32 degrees(d), minutes(m), seconds(s) 33 {} 34 }; 35 36 int main() { 37 // create and open a character archive for output 38 std::ofstream ofs("filename"); 39 40 // create class instance 41 const gps_position g(35, 59, 24.567f); 42 43 // save data to archive 44 { 45 boost::archive::text_oarchive oa(ofs); // compile error at here !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 46 // write class instance to archive 47 oa << g; 48 // archive and stream closed when destructors are called 49 } 50 51 // ... some time later restore the class instance to its orginal state 52 gps_position newg; 53 { 54 // create and open an archive for input 55 std::ifstream ifs("filename"); 56 boost::archive::text_iarchive ia(ifs); // compile error at here !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 57 // read class state from archive 58 ia >> newg; 59 // archive and stream closed when destructors are called 60 } 61 return 0; 62 } 63 ps2) compile error message (partly) /tmp/ccnNHOct.o: In function `boost::archive::text_iarchive& boost::smart_cast_impl::reference<boost::archive::text_iarchive&>::polymorphic::cross::cast<boost::archive::detail::basic_iarchive>(boost::archive::detail::basic_iarchive&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost15smart_cast_impl9referenceIRNS_7archive13text_iarchiveEE11polymorphic5cross4castINS2_6detail14basic_iarchiveEEES4_RT_+0x1b): undefined reference to `typeinfo for boost::archive::detail::basic_iarchive' /tmp/ccnNHOct.o: In function `boost::archive::text_oarchive& boost::smart_cast_impl::reference<boost::archive::text_oarchive&>::polymorphic::cross::cast<boost::archive::detail::basic_oarchive>(boost::archive::detail::basic_oarchive&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost15smart_cast_impl9referenceIRNS_7archive13text_oarchiveEE11polymorphic5cross4castINS2_6detail14basic_oarchiveEEES4_RT_+0x1b): undefined reference to `typeinfo for boost::archive::detail::basic_oarchive' /tmp/ccnNHOct.o: In function `void boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save<int>(int const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive18text_oarchive_implINS0_13text_oarchiveEE4saveIiEEvRKT_+0x15): undefined reference to `boost::archive::basic_text_oarchive<boost::archive::text_oarchive>::newtoken()' /tmp/ccnNHOct.o: In function `void boost::archive::save_access::save_primitive<boost::archive::text_oarchive, int>(boost::archive::text_oarchive&, int const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive11save_access14save_primitiveINS0_13text_oarchiveEiEEvRT_RKT0_+0x15): undefined reference to `boost::archive::detail::basic_oarchive::end_preamble()' /tmp/ccnNHOct.o: In function `void boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save<boost::archive::class_id_reference_type>(boost::archive::class_id_reference_type const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive18text_oarchive_implINS0_13text_oarchiveEE4saveINS0_23class_id_reference_typeEEEvRKT_+0x15): undefined reference to `boost::archive::basic_text_oarchive<boost::archive::text_oarchive>::newtoken()' /tmp/ccnNHOct.o: In function `void boost::archive::save_access::save_primitive<boost::archive::text_oarchive, boost::archive::class_id_reference_type>(boost::archive::text_oarchive&, boost::archive::class_id_reference_type const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive11save_access14save_primitiveINS0_13text_oarchiveENS0_23class_id_reference_typeEEEvRT_RKT0_+0x15): undefined reference to `boost::archive::detail::basic_oarchive::end_preamble()' /tmp/ccnNHOct.o: In function `void boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save<boost::archive::class_id_type>(boost::archive::class_id_type const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive18text_oarchive_implINS0_13text_oarchiveEE4saveINS0_13class_id_typeEEEvRKT_+0x15): undefined reference to `boost::archive::basic_text_oarchive<boost::archive::text_oarchive>::newtoken()' /tmp/ccnNHOct.o: In function `void boost::archive::save_access::save_primitive<boost::archive::text_oarchive, boost::archive::class_id_type>(boost::archive::text_oarchive&, boost::archive::class_id_type const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive11save_access14save_primitiveINS0_13text_oarchiveENS0_13class_id_typeEEEvRT_RKT0_+0x15): undefined reference to `boost::archive::detail::basic_oarchive::end_preamble()' /tmp/ccnNHOct.o: In function `void boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save<float>(float const&)': VerySimpleCase.cpp:(.gnu.linkonce.t._ZN5boost7archive18text_oarchive_implINS0_13text_oarchiveEE4saveIfEEvRKT_+0x15): undefined reference to `boost::archive::basic_text_oarchive<boost::archive::text_oarchive>::newtoken()'