How to fix “return value ignored: 'scanf'” code C6031 in visual studio

Question

I am brand new to coding C (and coding in general) so I have been practicing with some random programs. This one is supposed to determine the cost of a transit ticket (Trans

Answer 1

A bit too much here to put in a comment.

I use a version of Visual C but it never complains about the return value from scanf not being used. What it does is to complain that scanf is unsafe and deprecated, when it isn't.

MS thinks I should be using its own "safer" version scanf_s which is even tricker to use and IMO no safer at all – because it is not a like-for-like replacement but takes different arguments, and so it is easy to make mistakes in using it.

One consequent problem is the compiler issues a warning for every use of scanf (and some other functions) which obscures other warnings. I deal with it as advised by adding a #define before the first library header inclusion.

#define _CRT_SECURE_NO_WARNINGS

#include 

There are other matters which MS warns about too, and I actually place three #defines at the start of each file:

#define _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_DEPRECATE  
#define _CRT_NONSTDC_NO_DEPRECATE

#include 

And now the relevant warnings are easy to see.