How to print bits in c -

i'm writing function print bits in c, i'm allowed use write function. function doesn't work other numbers.

void    print_bits(unsigned char octet) {     int oct;     int div;      div = 128;     oct = octet;     while (!(div <= 1))     {         if (div <= oct)         {             write(1, "1", 1);             oct = oct % div;         }         else         {             write(1, "0", 1);             div = div / 2;         }     } } 

live code

i have re-written code is there printf converter print in binary format?

void    print_bits(unsigned char octet) {     int z = 128, oct = octet;      while (z > 0)     {         if (oct & z)             write(1, "1", 1);         else             write(1, "0", 1);         z >>= 1;     } }