Question

As everybody knows, you have limited precision when you use printf to output the value of a float.
However, there is a trick to increase the accuracy in the output, as this example shows:

#include <stdio.h>

int main()
{
    float f = 1318926965;        /* 10 random digits */
    printf("%10.f\n", f);        /* prints only 8 correct digits */
    printf("%10d\n", *(int*)&f); /* prints all digits correctly */
    return 0;
}

and my question is, why don’t people use this trick more often?

Answer 1

April fool?

Your “random number” 1318926965 have the same underlying representation both in decimal and floating-point form.

Try another value, like 10. It will print as:

        10
1092616192

So to answer your question:

and my question is, why don't people use this trick more often?

Because only one day of the year is April Fools Day… The rest of the days the trick doesn’t work…