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getsubopt

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#define _XOPEN_SOURCE 500
#include <stdlib.h>

int getsubopt(char **optionp, char *const *tokens, char valuep);

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ro,name=xyz

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*optionp ¤ÏÊѹ¹¤µ¤ì¤ë¤Î¤Ç¡¢ getsubopt() ¤ò¸Æ¤Ó½Ð¤¹Á°¤ÎºÇ½é¤Î¥µ¥Ö¥ª¥×¥·¥ç¥ó¤Ï getsubopt() ¤ò¸Æ¤Ó½Ð¤·¸å¤Î¥µ¥Ö¥ª¥×¥·¥ç¥ó¤Èɬ¤º¤·¤âƱ¤¸¤È¤Ï¸Â¤é¤Ê¤¤¡£

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POSIX.1-2001.

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getsubopt() ¤Ï¡¢Ê¸»úÎó *optionp Ãæ¤Ë¸«¤Ä¤±¤¿¥«¥ó¥Þ¤ò¾å½ñ¤­¤¹¤ë¤Î¤Ç¡¢Ê¸»úÎó *optionp ¤Ï½ñ¤­¹þ¤ß²Äǽ¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤º¡¢ ʸ»úÎóÄê¿ô¤Ë¤¹¤ë¤³¤È¤Ï¤Ç¤­¤Ê¤¤¡£

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#define _XOPEN_SOURCE 500

#include <stdlib.h>

#include <assert.h>

#include <stdio.h>



int main(int argc, char **argv)

{

    enum {

        RO_OPT = 0,

        RW_OPT,

        NAME_OPT

    };

    char *const token[] = {

        [RO_OPT]   = "ro",

        [RW_OPT]   = "rw",

        [NAME_OPT] = "name",

        NULL

    };

    char *subopts;

    char *value;

    int opt;



    int readonly = 0;

    int readwrite = 0;

    char *name = NULL;

    int errfnd = 0;



    while ((opt = getopt(argc, argv, "o:")) != -1) {

        switch(opt) {

        case 'o':

            subopts = optarg;

            while (*subopts != '\0' && !errfnd) {



            switch (getsubopt(&subopts, token, &value)) {

                case RO_OPT:

                    readonly = 1;

                    break;

        

                case RW_OPT:

                    readwrite = 1;

                    break;

        

                case NAME_OPT:

                    if (value == NULL) {

                        fprintf(stderr, "Missing value for "

                                "suboption '%s'\n", token[NAME_OPT]);

                        errfnd = 1;

                        continue;

                    }



                    name = value;

                    break;

        

                default:

                    fprintf(stderr, "No match found "

                            "for token: /%s/\n", value);

                    errfnd = 1;

                    break;

                }

            }

            if (readwrite && readonly) {

                fprintf(stderr, "Only one of '%s' and '%s' can be "

                        "specified\n", token[RO_OPT], token[RW_OPT]);

                errfnd = 1;

            }

            break;



        default:

            errfnd = 1;

        }

    }



    if (errfnd || argc == 1) {

        fprintf(stderr, "\nUsage: %s -o <suboptstring>\n", argv[0]);

        fprintf(stderr, "suboptions are 'ro', 'rw', "

                "and 'name=<value>'\n");

        exit(EXIT_FAILURE);

    }



    /* Remainder of program... */



    exit(EXIT_SUCCESS);

}

´ØÏ¢¹àÌÜ

getopt(3), feature_test_macros(7)