Get the current floating-point rounding direction
Synopsis:
#include <fenv.h>
int fegetround( void );
Library:
- libm
- The general-purpose math library.
- libm-sve
- (QNX Neutrino 7.1 or later)
A library that optimizes the code for ARMv8.2 chips that have Scalable Vector Extension hardware.
Your system requirements will determine how you should work with these libraries:
- If you want only selected processes to run with the SVE version, you can include both libraries in your OS image
and use the -l m or -l m-sve option to
qcc
to link explicitly against the appropriate one.
- If you want all processes to use the SVE version, include libm-sve.so in your OS image
and set up a symbolic link from libm.so to libm-sve.so.
Use the -l m option to
qcc
to link against the library.
Note:
Compile your program with the -fno-builtin option to prevent the compiler from using a
built-in version of the function.
Description:
The fegetround() function gets the current floating-point rounding direction.
The FLT_ROUNDS macro also returns the current rounding direction.
Returns:
- FE_DOWNWARD
- FE_TONEAREST
- FE_TOWARDZERO
- FE_UPWARD
- A negative value if the rounding direction couldn't be determined.
Classification:
C99,
POSIX 1003.1
Safety: |
|
Cancellation point |
No |
Interrupt handler |
Yes |
Signal handler |
Yes |
Thread |
Yes |