تجزیه آرگومان های خط فرمان در C

#include 
#include 
#include 
#include 

typedef struct {
    char* filepath;
    bool myflag;
    int myvalue;
} CliArgs;

static inline void error(const char* message) {
    fprintf(stderr, "%s\n", message);
    exit(1);
}

CliArgs parse(int argc, char** argv) {
    CliArgs cli_args = { .filepath = 0, .myflag = false, .myvalue = 0 };

    if (argc == 1)
        error("No argument was passed.");

    for (int i = 1; i < argc; ++i) {
        if (!strcmp(argv[i], "--myflag")) {
            cli_args.myflag = true;
            continue;
        }

        if (!strcmp(argv[i], "--myvalue")) {
            ++i;

            if (i == argc)
                error("No value passed for --myvalue.");

            char* str_end;
            cli_args.myvalue = strtol(argv[i], &str_end, 10);

            if (*str_end)
                error("Invalid value for --myvalue.");

            continue;
        }

        if (cli_args.filepath)
            error("Only a single filepath can be given.");
        else
            cli_args.filepath = argv[i];
    }

    if (!cli_args.filepath)
        error("No filepath was passed.");

    return cli_args;
}

int main(int argc, char** argv) {
    CliArgs cli_args = parse(argc, argv);

    printf("%s was called:\n", argv[0]);

    printf(
        "%s is the filepath, myflag is %s and myvalue is %i.\n",
        cli_args.filepath,
        cli_args.myflag ? "true" : "false",
        cli_args.myvalue
    );

    return 0;
}

$ gcc cli_args.c -o cli_args

$ ./cli_args 
No argument was passed.

$ ./cli_args foo.txt
./cli_args was called:
foo.txt is the filepath, myflag is false and myvalue is 0.

$ ./cli_args foo.txt --myvalue
No value passed for --myvalue.

$ ./cli_args foo.txt --myvalue bar
Invalid value for --myvalue.

$ ./cli_args foo.txt --myvalue 123
./cli_args was called:
foo.txt is the filepath, myflag is false and myvalue is 123.

$ ./cli_args foo.txt --myvalue 123 --myflag
./cli_args was called:
foo.txt is the filepath, myflag is true and myvalue is 123.