Upon successful completion, y0(), y1() and yn() will return the relevant Bessel value of x of the second kind.
If x is NaN, NaN is returned.
If the x argument to y0(), y1() or yn() is negative, -HUGE_VAL or NaN is returned, and errno may be set to EDOM.
If x is 0.0, -HUGE_VAL is returned and errno may be set to ERANGE or EDOM.
If the correct result would cause overflow, -HUGE_VAL is returned and errno may be set to ERANGE.
For exceptional cases, matherr(3M) tabulates the values to be returned as dictated
by Standards other than XPG4.