DragonFly On-Line Manual Pages

FEGETROUND(3)	      DragonFly Library Functions Manual	 FEGETROUND(3)

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 direc- tion 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 repre- sentable 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 direc- tion 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

feclearexcept(3), feenableexcept(3), fegetenv(3)

STANDARDS

The fegetround() and fesetround() functions conform to ISO/IEC 9899:1999 (``ISO C99'').

HISTORY

These functions first appeared in OpenBSD 5.0. DragonFly 4.3 June 5, 2013 DragonFly 4.3