Progge

Long time ago I wrote C. Could anyone fill me in why the first code snippet is arg parsing the way it is?

int main(int argc, char* argv[]) {

  if (argc > 1) {

    char\* r_loc = strchr(argv[1], 'r');

    if (r_loc != NULL) {

      ptrdiff_t r_from_start = (r_loc - argv[1]);

      if (r_from_start == 1 && argv[1][0] == '-' && strlen(r_loc) == 1) {
        in_reverse = 1;
      } 

    }

  }

  ...

}

Why not

if (argc > 1 && strcmp(argv[1], "-r") == 0) {

    in_reverse = 1;

}

for example?