what is responsible for input or taking user input from terminal C++\ code example

Example 1: c user input

#include <stdio.h>
int main()
{
    char chr;
    printf("Enter a character: ");
    scanf("%c",&chr);     
    printf("You entered %c.", chr);  
    return 0;
}

Example 2: get user input c

int c;
printf( "Enter a value :");
c = getchar( );