Hi, I am a newbie to Boost. I am writing a sample code using the Boost libaries and am getting the following error during linking. *Command Line Usage * * **g++ -I /usr/include/boost/ example.cpp -o example.o* *Code* *#include <boost/lambda/lambda.hpp> #include <iostream> #include <iterator> #include <algorithm> #include <boost/program_options/options_description.hpp> #include <boost/program_options/positional_options.hpp> #include <boost/program_options/variables_map.hpp> #include <boost/program_options/parsers.hpp> #include <cstdlib> #include <iostream> #include <iomanip> #include <map> #include <string> using namespace boost::program_options; //namespace po = boost::program_options; int main() { using namespace boost::lambda; // using namespace boost::program_options; typedef std::istream_iterator<int> in; std::for_each( in(std::cin), in(), std::cout << (_1 * 3) << " " ); option_description opts; } * *Error Message* /tmp/ccO0HWa7.o(.text+0xb0): In function `main': example.cpp: undefined reference to `boost::program_options::option_description::option_description()' /tmp/ccO0HWa7.o(.text+0xbf):example.cpp: undefined reference to `boost::program_options::option_description::~option_description()' collect2: ld returned 1 exit status $LD_LIBRARY_PATH has the following value set. /home/suhas/boost/lib:/usr/lib:/usr/include/boost/ I am stuck, any help will be really appreciated. Thanks in advance. Regards, Eswar