scanf not working when reading float

Question

I have the following code:

#include <stdio.h>

float a;            //Initialize variables
char b;
int c;
char d;

int main(void)
{
    printf("Enter float: ");
    scanf("%4.2f", &a);

    printf("%4.2f", a);

    //printf("Enter character:\n");

    //printf("Enter 4-digit integer: \n");

    //printf("Enter character:\n");

    return 0;
}

However I get the following errors when compiling:

1.) scanf:unknown field type character '.' in format specifier

2.) scanf: too many arguments passed for format string

Can anyone explain what the issue in my code is?

Thank you!

It still seems to have build errors when I try to compile. Hmmm.... — Froobyflake, Oct 13 '16 at 05:22
I posted the two errors above. The issue certainly has something to do with the scanf function. — Froobyflake, Oct 13 '16 at 05:26
That is exactly the code I have. What could be causing it to not work on my end? I am using Visual Studio 2015 — Froobyflake, Oct 13 '16 at 05:29
I used scanf_s instead and it worked! Why would scanf not work and scanf_s would? — Froobyflake, Oct 13 '16 at 05:32
http://stackoverflow.com/questions/30577519/error-c4996-scanf-this-function-or-variable-may-be-unsafe-in-c-programming this can answer all your queries. — sinsuren, Oct 13 '16 at 05:33

score 4 · Accepted Answer · edited May 23 '17 at 12:25

4

scanf("%f",&a) does not take format specifier.

As mentioned in comments Visual Studio treat this warning as error. So either use

scanf_s("%f",&a);

or go into settings and disable this warning as mentioned in this post Why does Visual Studio 2013 error on C4996?

edited May 23 '17 at 12:25

Community

1
1

answered Oct 13 '16 at 05:39

sinsuren

1,745
2
23
26

score 3 · Answer 2 · answered Oct 13 '16 at 05:37

3

You should not format the input. So just use %f as a first argument of scanf

scanf("%f", &a);

answered Oct 13 '16 at 05:37

score 1 · Answer 3 · answered Sep 19 '22 at 23:24

1

use %lf for scanning double precision inputs

answered Sep 19 '22 at 23:24

Johney

11
1

scanf not working when reading float

3 Answers3