how to check if the input is a number or not in C?

Question

In the main function of C:

void main(int argc, char **argv)
{
   // do something here
}

In the command line, we will type any number for ex

Answer 1

Using scanf is very easy, this is an example :

if (scanf("%d", &val_a_tester) == 1) {
    ... // it's an integer
}