fesetround(3M)fesetround(3M)NAMEfesetround() - set floating-point rounding direction mode
The function establishes the rounding direction represented by its
argument round. The round argument must equal one of the macros: and
If the argument does not match a rounding direction macro, the rounding
direction is not changed.
The default rounding direction mode is round to nearest
To use this function, compile either with the default option or with
the and options. Make sure your program includes
For HP Integrity servers, specify on the compiler command line or place
the call to this function under the effect of an affirmative pragma:
If the pragma is placed outside of any top-level declarations in a
file, the pragma will apply to all declarations in the compilation fol‐
lowing the pragma until another pragma is encountered or until the end
of the file is reached.
If the pragma is placed at the beginning of a block (compound state‐
ment), the pragma will apply until another pragma is encountered or
until the end of the block is reached.
For PA-RISC, you might need to use the compiler option in order to pre‐
vent optimizations that can undermine the specified behavior of this
Link in the math library by specifying on the compiler or linker com‐
For more information, see the at the following site:
The function returns a zero value if and only if the argument is equal
to a rounding direction macro.
No errors are defined.
Save, set, and restore the rounding direction.
SEE ALSOfegetround(3M), fenv(5).
: ISO/IEC C99 (including Annex F, "IEC 60559 floating-point arith‐