1-10-copy.c

#include <stdio.h>

int main()
{
  int c;

  while ((c = getchar()) != EOF) {
    if (c == '\t') {
      putchar('\\');
      putchar('t');
    } else if (c == '\b') {
      putchar('\\');
      putchar('b');
    } else if (c == '\\') {
      putchar('\\');
      putchar('\\');
    } else {
      putchar(c);
    }
  }
}