| NAME | SYNOPSIS | DESCRIPTION | CONFORMING TO | NOTES | EXAMPLE | SEE ALSO | COLOPHON | The Linux Programming Interface |
__SETFPUCW(3) Linux Programmer's Manual __SETFPUCW(3)
__setfpucw - set FPU control word on i386 architecture (obsolete)
#include <i386/fpu_control.h>
void __setfpucw(unsigned short control_word);
__setfpucw() transfers control_word to the registers of the FPU (floating-
point unit) on the i386 architecture. This was used to control floating-point
precision, rounding and floating-point exceptions.
This function was a nonstandard GNU extension.
As of glibc 2.1 this function does not exist anymore. There are new functions
from C99, with prototypes in <fenv.h>, to control FPU rounding modes, like
fegetround, fesetround, and the floating-point environment, like fegetenv,
feholdexcept, fesetenv, feupdateenv and FPU exception handling, like
feclearexcept, fegetexceptflag, feraiseexcept, fesetexceptflag, fetestexcept.
If direct access to the FPU control word is still needed, the _FPU_GETCW and
_FPU_SETCW macros from <fpu_control.h> can be used.
__setfpucw(0x1372)
Set FPU control word on the i386 architecture to
- extended precision
- rounding to nearest
- exceptions on overflow, zero divide and NaN
feclearexcept(3)
<fpu_control.h>
This page is part of release 3.32 of the Linux man-pages project. A
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at http://www.kernel.org/doc/man-pages/.
Linux 1997-03-08 __SETFPUCW(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface