getchar() with an unbuffered stdin

[Nwb]

#include <stdio.h>

int main() {

    setvbuf(stdin, NULL, _IONBF, 0);

    int input;
    input = getchar();

    printf("\n%c", input);

    return 0;
}

The setvbuf statement is supposed to disable the buffering for the stdin stream.
And getchar reads 1 character from the stdin.

So I expected this program to reach the printf statement as soon as I enter a character in the console.

But that does not happen. The program pauses at getchar and waits for it to read until I press the return_key. As though stdin is line buffered.

Why does that happen? Am I not allowed to change how the stdin is buffered?

[Salem]

Which OS/Compiler are you using?

How can I get input without having the user hit [Enter]? - Cprogramming.com

[Nwb]

Which OS/Compiler are you using?

I had just read about streams. I had read that the stdin was line buffered in my compiler. So I thought the reason getchar() didn't immediately read the character was because of this line buffering. I just wanted to clarify that.

How can I get input without having the user hit [Enter]? - Cprogramming.com

Thanks for the link. So the reason getchar() doesn't immediately read is not because of how stdin is buffered.. but a limitation of when input is added to the stdin..?

[Salem]

Depending on your platform, stdin can also be buffered in OS driver layer as well.

[Nwb]

I understood, thanks