Fast integer to decimal conversion

Question

Given an (unsigned) integer, what is the generally fastest way to convert it into a string that contains its decimal representation?

The naïve way of doing that

Answer 1

The MS version of printf does it the "naïve" way (after setting up a bunch of variables based on the optional flags):

            while (precision-- > 0 || number != 0) {
                digit = (int)(number % radix) + '0';
                number /= radix;                /* reduce number */
                if (digit > '9') {
                    /* a hex digit, make it a letter */
                    digit += hexadd;
                }
                *text.sz-- = (char)digit;       /* store the digit */
            }