Multiply a floating-point number by an integral power of FLT_RADIX.
double __far scalbln(double x, long int n); (C99)
Returns the value calculated by x x FLT_RADIXn.
When x is a Not-a-Number (NaN), scalbln returns a Not-a-Number (NaN) and sets macro EDOM to global variable errno.
If an underflow or overflow occurs as a result of executing scalbln, it sets macro ERANGE to global variable errno. If an underflow occurs, scalbln returns an denormal number. If an overflow occurs, it returns ∞.
Multiply a floating-point number by an integral power of FLT_RADIX.