Divide Executable with Parameters through cmd in c not working

Question

I'm trying to create a neural network using a batch file. The only problem is that batch doesn't support floating point numbers. So, I decided to make an executable in c in which you could pass in 2+ parameters, for example: "divide 5 3" in the cmd, and it would divide the parameters. Here is my program:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char* argv[]) {
    float num1 = atoi(argv[1]);
    float num2 = atoi(argv[2]);
    if (argc > 2) {
        printf("%f", num1 / num2);
        return EXIT_SUCCESS;
    }
    else {
        printf("3 arguments expected\n");
        return EXIT_FAILURE;
    }
}

Of course, this doesn't work, and yes, I have tried to change the numbers a bit and made countless versions of this program. I couldn't find a solution online. Last time you guys helped me a lot, hope you can again!

Answer 1

Adding a newline to the output and running it:

$ ./div
Segmentation fault
$ ./div 1
Segmentation fault
$ ./div 1 3
0.333333

You're reading from argv[1] and argv[2] before checking argc to see how many arguments you have.

With zero or one arguments one or both of them will contain garbage, which not surprisingly leads to a segfault when it tries to read from some random location. (Or maybe there was a guaranteed NULL at the end of argv . I can't remember, but it doesn't matter, you still get a segfault.)

Regarding that error message, I would say "2 arguments expected", not 3, since usually the user won't count the program name, even though the number in argc includes it.