我注意到大多数GNU核心应用程序的基本“样式”,其中参数为:
--longoption
--longoption=value
--longoption value
-abcdefg
-iuwww-data
i
u = www-data
他们遵循上述样式。我想避免编写参数解析器,如果有一个使用上述样式的库可以做到这一点。你知道吗?
getopt_long将完成这项工作,这是来自http://www.gnu.org/s/libc/manual/html_node/Getopt- Long-Option-Example.html的示例
#include <stdio.h> #include <stdlib.h> #include <getopt.h> /* Flag set by ‘--verbose’. */ static int verbose_flag; int main (argc, argv) int argc; char **argv; { int c; while (1) { static struct option long_options[] = { /* These options set a flag. */ {"verbose", no_argument, &verbose_flag, 1}, {"brief", no_argument, &verbose_flag, 0}, /* These options don't set a flag. We distinguish them by their indices. */ {"add", no_argument, 0, 'a'}, {"append", no_argument, 0, 'b'}, {"delete", required_argument, 0, 'd'}, {"create", required_argument, 0, 'c'}, {"file", required_argument, 0, 'f'}, {0, 0, 0, 0} }; /* getopt_long stores the option index here. */ int option_index = 0; c = getopt_long (argc, argv, "abc:d:f:", long_options, &option_index); /* Detect the end of the options. */ if (c == -1) break; switch (c) { case 0: /* If this option set a flag, do nothing else now. */ if (long_options[option_index].flag != 0) break; printf ("option %s", long_options[option_index].name); if (optarg) printf (" with arg %s", optarg); printf ("\n"); break; case 'a': puts ("option -a\n"); break; case 'b': puts ("option -b\n"); break; case 'c': printf ("option -c with value `%s'\n", optarg); break; case 'd': printf ("option -d with value `%s'\n", optarg); break; case 'f': printf ("option -f with value `%s'\n", optarg); break; case '?': /* getopt_long already printed an error message. */ break; default: abort (); } } /* Instead of reporting ‘--verbose’ and ‘--brief’ as they are encountered, we report the final status resulting from them. */ if (verbose_flag) puts ("verbose flag is set"); /* Print any remaining command line arguments (not options). */ if (optind < argc) { printf ("non-option ARGV-elements: "); while (optind < argc) printf ("%s ", argv[optind++]); putchar ('\n'); } exit (0); }