comparing version numbers in c

Question

I am seeing a lot of answers for this problem in other languages but I am trying to find out a way to compare 2 version numbers given as strings. For example

Answer 1

I know I wont be able to tokenize 2 strings at once.

Fortunately, you do not need to: make a function that takes a string, and parses it for three integer numbers using strtok_r (use a reentrant version, it's a lot safer).

strunct version_t {
    int major;
    int minor;
    int build;
};

version_t parse_ver(const char* version_str) {
    version_t res;
    // Use strtok_r to split the string, and atoi to convert tokens to ints
    return res;
}

Now you can call parse_ver twice, get two version_t values, and compare them side-by-side.

P.S. If you adopt a convention to always pad the numbers with leading zeros to a specific length, i.e. make sure that you write "141.1.03" and not "141.1.3", you could substitute integer comparison with lexicographic one.