<cfenv> (fenv.h)

Floating-point environment
This header declares a set of functions and macros to access the floating-point environment, along with specific types.

The floating-point environment maintains a series of status flags and specific control modes. Specific about the contents of the floating-point environment depend on the implementation, but the status flags generally include the floating-point exceptions and their associated information, and the control modes include at least the rounding direction.


Floating-point exceptions

Rounding direction

Entire environment


Macro constants

Floating-point exceptions

Rounding directions

Entire evnironment