For example, IEEE_NEXT_UP(-0.0) and IEEE_NEXT_UP(+0.0) both return the smallest positive subnormal value (provided subnormal values are supported), without signalling IEEE_UNDERFLOW (which IEEE_NEXT_AFTER does).
Similarly, IEEE_NEXT_UP(HUGE(0.0)) returns +∞ without signalling overflow.
For example,
USE F90_KIND USE IEEE_ARITHMETIC LOGICAL(byte) flags(SIZE(IEEE_ALL)) CALL IEEE_GET_FLAG(IEEE_ALL,flags)will retrieve the current IEEE flags into an array of one-byte LOGICALs.