program_options 使用示例

#include <boost/program_options.hpp>
#include <string>
#include <stdint.h>
#include <iostream>
#include <stdio.h>

using namespace std;
namespace po = boost::program_options;

int main(int argc, char **argv)
{
    string ip;
    uint32_t port;
    string ext_flag;

    po::variables_map opts_varmap;
    po::options_description desc("program desc");
    desc.add_options()
        ("ip,i", po::value<string>(&ip), "first param is ip")
        ("port,p", po::value<uint32_t>(&port), "second param is port")
        ("ext_flag,e", po::value<string>(&ext_flag)->default_value(""), "ext flag")
        ("help,h", "help")
        ;
    
    // position param
    po::positional_options_description pos_desc;
    pos_desc.add("ip", 1);
    pos_desc.add("port", 1);

    try {
        po::store(po::command_line_parser(argc, argv).options(desc).positional(pos_desc).run(), opts_varmap);
        po::notify(opts_varmap);
    } catch(std::exception &e) {
        cout << e.what() << std::endl;
        return -1;
    }

    if(opts_varmap.count("help")) {
        cout << desc << endl;
        return 0;
    }
    printf("input param: ip=%s, port=%u, ext_flag=%s\n", ip.c_str(), port, ext_flag.c_str());
}

使用：

$ ./program_options_demo  -i 127.0.0.1  -p 9999  -e flag1
input param: ip=127.0.0.1, port=9999, ext_flag=flag1

$ ./program_options_demo  127.0.0.1  9999  -e flag1
input param: ip=127.0.0.1, port=9999, ext_flag=flag1

$ ./program_options_demo  -e flag1  127.0.0.1  9999  
input param: ip=127.0.0.1, port=9999, ext_flag=flag1

$ ./program_options_demo  
input param: ip=, port=0, ext_flag=

$ ./program_options_demo -h
program desc:
  -i [ --ip ] arg       first param is ip
  -p [ --port ] arg     second param is port
  -e [ --ext_flag ] arg ext flag
  -h [ --help ]         help