NAME
fegetround,
fesetround —
control floating-point rounding
direction modes
SYNOPSIS
#include
<fenv.h>
int
fegetround(void);
int
fesetround(int
round);
DESCRIPTION
These functions provide control of floating-point rounding direction modes. The round input argument is a value specifying a rounding direction mode and containing any of the values listed below.
FE_TONEAREST- Results are rounded to the closest representable value. If the exact result is exactly half way between two representable values, the value whose last binary digit is even (zero) is chosen. This is the default mode.
FE_DOWNWARD- Results are rounded towards negative infinity.
FE_UPWARD- Results are rounded towards positive infinity.
FE_TOWARDZERO- Results are rounded towards zero.
The
fegetround()
function gets the current rounding direction.
The
fesetround()
function establishes the rounding direction represented by
round. If the argument is not equal to the value of
a rounding direction macro, the rounding direction is not changed.
RETURN VALUES
The fegetround() function returns the
current rounding direction. The fesetround()
function return zero on success, and non-zero if an error occurred.
SEE ALSO
STANDARDS
The fegetround() and
fesetround() functions conform to
ISO/IEC 9899:1999
(“ISO C99”).
HISTORY
These functions first appeared in OpenBSD 5.0.