#define no_argument        0
#define required_argument  1
#define optional_argument  2

struct option {
   const char *name;   //名称,下面实例中使用的--help，--version
   int has_arg;        //是否有参数,可选0,1,2三个值，就是上面的那三个宏定义
   int *flag;          //返回值，传入的一个int指针，表示该参数的解析结果，如果是NULL，那么返回值就会被写到getopt_long的返回值中。
   int val;            //name的简写
};

#include <unistd.h>

int getopt(int argc, char * const argv[],const char *optstring);
extern char *optarg;
extern int optind, opterr, optopt;

#include <getopt.h>
    int getopt_long(int argc, char * const argv[],
    const char *optstring,
    const struct option *longopts, 
    int *longindex);

int getopt_long_only(int argc, char * const argv[],
    const char *optstring,
    const struct option *longopts, 
    int *longindex);

#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <iostream>
using namespace std;

int discovery_options(int argc, char** argv, bool& show_help, bool& show_version,string& input)
{
    int ret = 0;
    
    static option long_options[] = {
        {"help", no_argument, &ret, ‘h‘},
        {"version", no_argument, 0, ‘v‘},
        {"arga", required_argument , 0, ‘a‘},
        {"argb", required_argument , 0, ‘b‘},
        {0, 0, 0, 0}
    };
    
    int opt = 0;
    int option_index = 0;
    while((opt = getopt_long(argc, argv, "hva:b:", long_options, &option_index)) != -1){
        switch(opt){
        case ‘h‘:
                show_help = true;
                break;
        case ‘v‘:
                show_version = true;
                break;
        case ‘a‘:
                input = optarg;
                break;
        case ‘b‘:
                input = optarg;
                break;
            default:
                show_help = true;
                break;
        }
    }
    // check values

    return ret;
}

void help(char** argv){
    printf("%s, Copyright (c) 2013-2015 BuguTian\n", argv[0]);
    printf(""
        "Usage: %s <Options> <-a REQUEST>\n"
        "-h no arg,mean help\n"
        "-v no arg,mean version\n"
        "-a arga\n"
        "-b argb\n",
        argv[0]);
        
    exit(0);
}
void version()
{
    printf("V1.1.1\n");
    exit(0);
}

int main(int argc, char** argv){
    int ret = 0;
    bool show_help = false;
    bool show_version = false;
    string input="";
    if((ret = discovery_options(argc, argv, show_help, show_version, input))){
        printf("discovery options failed. ret=%d", ret);
        return ret;
    }
    if(show_help){
        help(argv);
    }
    if(show_version){
        version();
    }
    printf("running...\n");
    return 0;
}