Link error in Boost program_options code on Ubuntu

Question

I installed boost on ubuntu 10.04 by

sudo apt-get install libboost-dev

I think after that I don\'t need to set any -I and -L flags, so I co

Answer 1

You need to link to the Boost program_options library as not everything in Boost is pure templates:

edd@max:/tmp$ cat bpoex.cpp 
#include <iostream>
#include <string>
#include <set>
#include <sstream>

#include <boost/config.hpp>
#include <boost/program_options/detail/config_file.hpp>
#include <boost/program_options/parsers.hpp>

namespace pod = boost::program_options::detail;

int main() 
{  
    //contents
    std::stringstream s(
            "a = 1\n"
            "b = 2\n"
            "c = test option\n");
    //parameters
    std::set<std::string> options;
    options.insert("a");
    options.insert("b");
    options.insert("c");

    //parser
    for (pod::config_file_iterator i(s, options), e ; i != e; ++i)
    {
        std::cout << i->value[0] << std::endl;
    }
}
edd@max:/tmp$ g++ -o bpoex bpoex.cpp -lboost_program_options
edd@max:/tmp$ ./bpoex
1
2
test option
edd@max:/tmp$