fflush() is not working in Linux

Question

I used the fflush() in Linux GCC but it did not work. Are there any alternatives for that function? Here is my code:

#include
void main()
{
           


        

Answer 1

#include<stdio.h>
int main()
{
char ans='y';
int a;
while(ans=='y'||ans=='Y')
    {

     printf("Type a number:-");
     scanf("%d",&a);
     printf("square of number = %d\nwant to enter 
     number again(y/n)?\nANS=",a*a); 
     scanf("%s",&ans);//use %s in place of %c
     }
return 0;
}

Answer 2

Use getchar() instead, after scanf

Answer 3

One that always works on Linux:

#include <termios.h>
#include <unistd.h>

void clean_stdin()
{
        int stdin_copy = dup(STDIN_FILENO);
        /* remove garbage from stdin */
        tcdrain(stdin_copy);
        tcflush(stdin_copy, TCIFLUSH);
        close(stdin_copy);
}

You can use tcdrain and tcflush not only for in/out/err fd.