getopt测试

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
char *l_opt_arg;
char* const short_options = "ht:";
struct option long_options[] = { { "help", 0, NULL, 'h' }, { "time", 1, NULL,
        't' }, { 0, 0, 0, 0 }, };
void useage() {
    printf("Usage:"
        "\ttime_tool --help -h\n"
        "\ttime_tool 12:00\n");
}
void output(char *Time) {
    time_t t;
    struct tm p_t;
    char Tmp[200];
    int i = 1;
    time(&t);
    localtime_r(&t, &p_t);
    if (Time != NULL) {
        sscanf(Time, "%d:%d", &p_t.tm_hour, &p_t.tm_min);
    }
    for (i = 1; i < 11; i++) {
        p_t.tm_min += 1;
        p_t.tm_min %= 60;
        memset(Tmp, 0, sizeof(Tmp));
        if (strftime(Tmp, sizeof(Tmp), "%H:%M", &p_t) == 0) {
            fprintf(stderr, "strftime returned 0");
            exit(EXIT_FAILURE);
        }

        if (i % 2 == 0) {
            printf("-");
        } else {
            if (i != 1)
                printf(",");
        }
        printf("%s", Tmp);
    }
    printf("\n");
}
int main(int argc, char **argv) {
    int c = 0;
    while ((c = getopt_long(argc, argv, short_options, long_options, NULL))
            != -1) {
        switch (c) {
        case 'h':
            useage();
            return 0;
        case 't':
            l_opt_arg = optarg;
            output(l_opt_arg);
            return 0;
        }
    }
    if (c == -1) {
        output(NULL);
    }
    return 0;
}