1__setfpucw(3) Library Functions Manual __setfpucw(3)
2
3
4
6 __setfpucw - set FPU control word on i386 architecture (obsolete)
7
9 Standard C library (libc, -lc)
10
12 #include <i386/fpu_control.h>
13
14 [[deprecated]] void __setfpucw(unsigned short control_word);
15
17 __setfpucw() transfers control_word to the registers of the FPU (float‐
18 ing-point unit) on the i386 architecture. This was used to control
19 floating-point precision, rounding and floating-point exceptions.
20
22 GNU.
23
25 Removed in glibc 2.1.
26
28 There are new functions from C99, with prototypes in <fenv.h>, to con‐
29 trol FPU rounding modes, like fegetround(3), fesetround(3), and the
30 floating-point environment, like fegetenv(3), feholdexcept(3), fes‐
31 etenv(3), feupdateenv(3), and FPU exception handling, like feclearex‐
32 cept(3), fegetexceptflag(3), feraiseexcept(3), fesetexceptflag(3), and
33 fetestexcept(3).
34
35 If direct access to the FPU control word is still needed, the
36 _FPU_GETCW and _FPU_SETCW macros from <fpu_control.h> can be used.
37
39 __setfpucw(0x1372)
40
41 Set FPU control word on the i386 architecture to
42 • extended precision
43 • rounding to nearest
44 • exceptions on overflow, zero divide and NaN
45
47 feclearexcept(3)
48
49 <fpu_control.h>
50
51
52
53Linux man-pages 6.05 2023-03-30 __setfpucw(3)