1__setfpucw(3)              Library Functions Manual              __setfpucw(3)
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NAME

6       __setfpucw - set FPU control word on i386 architecture (obsolete)
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LIBRARY

9       Standard C library (libc, -lc)
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SYNOPSIS

12       #include <i386/fpu_control.h>
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14       [[deprecated]] void __setfpucw(unsigned short control_word);
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DESCRIPTION

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.
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STANDARDS

22       GNU.
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HISTORY

25       Removed in glibc 2.1.
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NOTES

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).
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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.
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EXAMPLES

39       __setfpucw(0x1372)
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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
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SEE ALSO

47       feclearexcept(3)
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49       <fpu_control.h>
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53Linux man-pages 6.04              2023-03-30                     __setfpucw(3)