For some reason, I'm having a hard time trying to cover the block of code below. This code is an excerpt from the UNIX uniq command. I'm trying to write test cases to cover all blocks, but can't seem to reach this block:

if (nfiles == 2)
{
    // Generic error routine
}

In context:

int main (int argc, char **argv)
{
    int optc = 0;
    bool posixly_correct = (getenv ("POSIXLY_CORRECT") != NULL);
    int nfiles = 0;
    char const *file[2];

    file[0] = file[1] = "-";
    program_name = argv[0];

    skip_chars = 0;
    skip_fields = 0;
    check_chars = SIZE_MAX;

    for (;;)
    {
        /* Parse an operand with leading "+" as a file after "--" was
        seen; or if pedantic and a file was seen; or if not
        obsolete.  */

        if (optc == -1 || (posixly_correct && nfiles != 0) || ((optc = getopt_long (argc, argv, "-0123456789Dcdf:is:uw:", longopts, NULL)) == -1))
        {
            if (optind == argc)
                break;
            if (nfiles == 2)
            {
                // Handle errors
            }
            file[nfiles++] = argv[optind++];
        }
        else switch (optc)
        {
            case 1:
            {
                unsigned long int size;
                if (optarg[0] == '+' && posix2_version () < 200112 && xstrtoul (optarg, NULL, 10, &size, "") == LONGINT_OK && size <= SIZE_MAX)
                    skip_chars = size;
                else if (nfiles == 2)
                {
                    // Handle error
                }
                else
                    file[nfiles++] = optarg;
            }
            break;
        }
    }
}

Any help would be greatly appreciated. Thanks.