1 // Copyright Vladimir Prus 2002-2004.
2 // Distributed under the Boost Software License, Version 1.0.
3 // (See accompanying file LICENSE_1_0.txt
4 // or copy at http://www.boost.org/LICENSE_1_0.txt)
5
6 /* Shows how to use both command line and config file. */
7
8 #include <boost/program_options.hpp>
9 namespace po = boost::program_options;
10
11
12 #include <iostream>
13 #include <fstream>
14 #include <iterator>
15 using namespace std;
16
17 // A helper function to simplify the main part.
18 template<class T>
operator <<(ostream & os,const vector<T> & v)19 ostream& operator<<(ostream& os, const vector<T>& v)
20 {
21 copy(v.begin(), v.end(), ostream_iterator<T>(os, " "));
22 return os;
23 }
24
25
main(int ac,char * av[])26 int main(int ac, char* av[])
27 {
28 try {
29 int opt;
30 string config_file;
31
32 // Declare a group of options that will be
33 // allowed only on command line
34 po::options_description generic("Generic options");
35 generic.add_options()
36 ("version,v", "print version string")
37 ("help", "produce help message")
38 ("config,c", po::value<string>(&config_file)->default_value("multiple_sources.cfg"),
39 "name of a file of a configuration.")
40 ;
41
42 // Declare a group of options that will be
43 // allowed both on command line and in
44 // config file
45 po::options_description config("Configuration");
46 config.add_options()
47 ("optimization", po::value<int>(&opt)->default_value(10),
48 "optimization level")
49 ("include-path,I",
50 po::value< vector<string> >()->composing(),
51 "include path")
52 ;
53
54 // Hidden options, will be allowed both on command line and
55 // in config file, but will not be shown to the user.
56 po::options_description hidden("Hidden options");
57 hidden.add_options()
58 ("input-file", po::value< vector<string> >(), "input file")
59 ;
60
61
62 po::options_description cmdline_options;
63 cmdline_options.add(generic).add(config).add(hidden);
64
65 po::options_description config_file_options;
66 config_file_options.add(config).add(hidden);
67
68 po::options_description visible("Allowed options");
69 visible.add(generic).add(config);
70
71 po::positional_options_description p;
72 p.add("input-file", -1);
73
74 po::variables_map vm;
75 store(po::command_line_parser(ac, av).
76 options(cmdline_options).positional(p).run(), vm);
77 notify(vm);
78
79 ifstream ifs(config_file.c_str());
80 if (!ifs)
81 {
82 cout << "can not open config file: " << config_file << "\n";
83 return 0;
84 }
85 else
86 {
87 store(parse_config_file(ifs, config_file_options), vm);
88 notify(vm);
89 }
90
91 if (vm.count("help")) {
92 cout << visible << "\n";
93 return 0;
94 }
95
96 if (vm.count("version")) {
97 cout << "Multiple sources example, version 1.0\n";
98 return 0;
99 }
100
101 if (vm.count("include-path"))
102 {
103 cout << "Include paths are: "
104 << vm["include-path"].as< vector<string> >() << "\n";
105 }
106
107 if (vm.count("input-file"))
108 {
109 cout << "Input files are: "
110 << vm["input-file"].as< vector<string> >() << "\n";
111 }
112
113 cout << "Optimization level is " << opt << "\n";
114 }
115 catch(exception& e)
116 {
117 cout << e.what() << "\n";
118 return 1;
119 }
120 return 0;
121 }
122