Set of functions to manipulate bit in C language

c_bitwise_functions.c

int is_bit_i_set(unsigned char c, int i) {
  unsigned char mask = 1 << i;
  return mask & c;
}

void set_bit(unsigned char *c, int i) {
  *c |= 1 << i;
}

void clear_byte(unsigned char *byte) {
  int i;

  for(i = 7; i >= 0; --i) {
    *byte &= ~(1 << i);
  }
}