c/string/byte/strfromf

Converts a floating-point value to a byte string.

The functions are equivalent to, except that the format string shall only contain the character , an optional precision that does not contain an asterisk , and one of the conversion specifiers , , , , , , , or , which applies to the type , , or ) indicated by the function suffix (rather than by a length modifier). Use of these functions with any other format string results in undefined behavior.

Return value
The number of characters that would have been written had been sufficiently large, not counting the terminating null character. Thus, the null-terminated output has been completely written if and only if the returned value is both nonnegative and less than.