infnan - deal with infinite or not-a-number (NaN) result

SYNOPSIS

       #include <math.h>

       double infnan(int error);

DESCRIPTION

       The  infnan() function returns a suitable value for infin­
       ity and "not-a-number" (NaN) results.  The value of  error
       can  be  ERANGE  to represent infinity or anything else to
       represent NaN.  errno is also set.

RETURN VALUE

       If error is ERANGE (Infinity), HUGE_VAL is returned.

       If error is -ERANGE (-Infinity), -HUGE_VAL is returned.

       If error is anything else, NAN is returned.

ERRORS

       ERANGE The value of error is positive or  negative  infin­
              ity.

       EDOM   The value of error is "not-a-number" (NaN).

CONFORMING TO

       BSD 4.3