Question

I was testing with c language today and I made two small c files

main.c

#include<conio.h>
void testing();
int main()
{
    testing();
    getch();
    return 0;
}

testing.c

#include <stdio.h>

void testing()
{
    char ch;
    printf("Hello Testing\n");
    do{
        printf("Enter Character : ");
        ch=getchar();
        printf("You Entered : %c\n",ch);
        testing();
        }while(ch!='N');
}

The problem I am facing is it read one character from user and then it loop twice and I don’t know why

output
Hello Testing
Enter Character : k //(i entered k)
You Entered : k

Hello Testing// why this is displayed twice??
Enter Character : You Entered :// i don't press any key and it moves to next iteration

Hello Testing
Enter Character : // here i can enter character again and it happens again twice

I have complied it on Visual Studio 2012.

Answer 1

Because getchar() leaves a newline character in the input buffer. You can use another getchar() to eat the newline.

ch=getchar();
getchar();

Or use scanf to eat leading whitespaces:

scanf(" %c", &ch);

This way all the previous \n will be ignored.