请教getopt_long_only()函数的问题？

[jackydi]

这个函数不能使用大写字母的短选项吗？
看下面的代码：

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <unistd.h>
#include <getopt.h>

static struct option long_options[] =
{
    {"reqarg", required_argument,   NULL, 'r'},
    {"optarg", optional_argument,   NULL, 'o'},
    {"noarg1", required_argument,   NULL, 'N'},
    {"noarg",  required_argument,   NULL, 'n'},
    {NULL,     0,                   NULL, 0},
};

int main(int argc, char *argv[])
{
    int opt;
    int digit_optind = 0;
    int option_index = 0;
    char *string = "A::b:c:N";
    while((opt =getopt_long_only(argc,argv,string,long_options,&option_index))!= -1)
    {
        printf("opt = %c\t\t", opt);
        printf("optarg = %s\t\t",optarg);
        printf("optind = %d\t\t",optind);
        printf("argv[optind] =%s\t\t", argv[optind]);
        printf("option_index = %d\n",option_index);
    }
}

在命令行中直接结果如下：

# ./t -r 324 -n 234 -N asdf
opt = r optarg = 324 optind = 3 argv[optind] =-n option_index = 0
./t: option '-n' is ambiguous
opt = ? optarg = (null) optind = 4 argv[optind] =234 option_index = 0
./t: unrecognized option '-N'
opt = ? optarg = (null) optind = 6 argv[optind] =asdf option_index = 0

为啥会有这两个红色字体的显示？struct option long_options[] 中不能定义大写字母的短选项值吗？

[chenls_JL]

楼主的问题解决了吗。能分享下嘛。