__SETFPUCW(3) Linux Programmer's Manual __SETFPUCW(3)
NAME
__setfpucw - set fpu control word on i386 architecture (obsolete)
SYNOPSIS
#include <i386/fpu_control.h>
void __setfpucw((unsigned short) control_word);
DESCRIPTION
__setfpucw transfers control_word to the registers of the fpu (floating point unit) on i386 architecture. This was used to control floating
point precision, rounding and floating point exceptions.
EXAMPLE
__setfpucw(0x1372)
Set fpu control word on i386 architecture to
- extended precision
- rounding to nearest
- exceptions on overflow, zero divide and NaN
AVAILABILITY
As of glibc 2.1 this function does not exist anymore. There are new functions from ISO C99, with prototypes in /usr/include/fenv.h, to
control fpu rounding modes, like fegetround, fesetround, and the floating point environment, like fegetenv, feholdexcept, fesetenv, feupda-
teenv and fpu exception handling, like feclearexcept, fegetexceptflag, feraiseexcept, fesetexceptflag, fetestexcept.
If direct acces to the FPU control word is still needed, the _FPU_GETCW and _FPU_SETCW macros from /usr/include/fpu_control.h can be used.
SEE ALSO
feclearexcept(3)
/usr/include/i386/fpu_control.h
i386 Linux Man Page 1997-03-08 __SETFPUCW(3)
