Print float/double without trailing zeros? [duplicate]

Question

There are a few questions related to this, but I haven't seen one that correctly answers this question. I want to print a floating-point number, but I want the number of decimal places to be adaptive. As an example:

0      -> 0
1234   -> 1234
0.1234 -> 0.1234
0.3    -> 0.3

Annoyingly, the %f specifier will only print to a fixed precision, so it will add trailing zeros to all numbers that don't reach that precision. Some have suggested the %g specifier, which works for a set of numbers, but it will switch to scientific notation for some numbers, like this:

printf("%g", 1000000.0); // prints 1e+06

How can I print floating-point numbers without the unnecessary zeros, while still maintaining printf's standard accuracy for numbers that actually have fractional components?

Answer 1

Use snprintf to print to a temporary buffer then remove the trailing '0' characters manually. There is no other way that's both correct and reasonably easy to implement.