__SETFPUCW

__setfpucw ? set fpu control word on i386 architecture

#include <i386/fpu_control.h>

void __setfpucw((unsigned short) control_word);

__setfpucw transfer control_word to the registers of the fpu (floating point unit) on i386 architecture. This can be used to control floating point precision, rounding and floating point exceptions.

__setfpucw(0x1372)

Set fpu control word on i386 architecture to
- extended precision
- rounding to nearest
- exceptions on overflow, zero divide and NaN

/usr/include/i386/fpu_control.h