Avoid trailing zeroes in printf()

Question

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

Answer 1

Here is my first try at an answer:

void
xprintfloat(char *format, float f)
{
  char s[50];
  char *p;

  sprintf(s, format, f);
  for(p=s; *p; ++p)
    if('.' == *p) {
      while(*++p);
      while('0'==*--p) *p = '\0';
    }
  printf("%s", s);
}

Known bugs: Possible buffer overflow depending on format. If "." is present for other reason than %f wrong result might happen.

Answer 2

I would say you should use printf("%.8g",value);

If you use "%.6g" you will not get desired output for some numbers like.32.230210 it should print 32.23021 but it prints 32.2302