I keep stumbling on the format specifiers for the printf() family of functions. What I want is to be able to print a double (or float) with a maximum given number of digits
To get rid of the trailing zeros, you should use the "%g" format:
float num = 1.33;
printf("%g", num); //output: 1.33
After the question was clarified a bit, that suppressing zeros is not the only thing that was asked, but limiting the output to three decimal places was required as well. I think that can't be done with sprintf format strings alone. As Pax Diablo pointed out, string manipulation would be required.