The header file math.h consists of a macro and various functions
that calculate common mathematical operations. Error conditions may be handled with a
domain error or range error (see errno.h).
A domain error occurs when the input argument is outside the domain over
which the function is defined. The error is reported by storing the value of
EDOM in errno and returning a particular value
defined for each function.
A range error occurs when the result is too large or too small to be
represented in the target precision. The error is reported by storing the value of
ERANGE in errno and returning
HUGE_VAL if the result overflowed (return value was too large) or a
zero if the result underflowed (return value is too small).
Responses to special values, such as NaNs, zeros and infinities, may vary depending upon the function. Each function description includes a definition of the function’s response to such values.