Usar o Backspace em C

#include <stdio.h>
#include <termios.h>

#define OFF 0
#define ON 1

void echo(short int s){

static short int e_flag = 0;
static int t_flag = 0;
static struct termios t_new;

if (!e_flag) {
e_flag = 1;
tcgetattr(0, &t_new);
t_flag = t_new.c_lflag;
}

if (s==0) t_new.c_lflag &= ~ECHO;
else t_new.c_lflag = t_flag;
if (s==1) t_new.c_lflag &= ~ICANON;

tcsetattr(0, TCSANOW, &t_new);

return;

}

int main (void){

char a, b, c;

__fpurge(stdin);
putc('x',stdout);
read(0,&a,1);

echo(0);

__fpurge(stdin);
putc('y',stdout);
read(0,&b,1);;

echo(1);

__fpurge(stdin);
putc('z',stdout);
read(0,&c,1);

printf("a=%c; b=%c; c=%c\n", a, b, c);

return 0;

}