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diff --git a/static/freebsd/man3/fpgetround.3 4.html b/static/freebsd/man3/fpgetround.3 4.html new file mode 100644 index 00000000..4547c0b3 --- /dev/null +++ b/static/freebsd/man3/fpgetround.3 4.html @@ -0,0 +1,161 @@ +<table class="head"> + <tr> + <td class="head-ltitle">FPGETROUND(3)</td> + <td class="head-vol">Library Functions Manual</td> + <td class="head-rtitle">FPGETROUND(3)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">fpgetround</code>, + <code class="Nm">fpsetround</code>, <code class="Nm">fpsetprec</code>, + <code class="Nm">fpgetprec</code>, <code class="Nm">fpgetmask</code>, + <code class="Nm">fpsetmask</code>, <code class="Nm">fpgetsticky</code>, + <code class="Nm">fpresetsticky</code> — <span class="Nd">IEEE + floating point interface</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="In">#include + <<a class="In">ieeefp.h</a>></code></p> +<div class="Bd Pp Li"> +<pre>typedef enum { + FP_RN, /* round to nearest */ + FP_RM, /* round down to minus infinity */ + FP_RP, /* round up to plus infinity */ + FP_RZ /* truncate */ +} fp_rnd_t;</pre> +</div> +<br/> +<var class="Ft">fp_rnd_t</var> +<br/> +<code class="Fn">fpgetround</code>(<var class="Fa" style="white-space: nowrap;">void</var>); +<p class="Pp"><var class="Ft">fp_rnd_t</var> + <br/> + <code class="Fn">fpsetround</code>(<var class="Fa" style="white-space: nowrap;">fp_rnd_t + direction</var>);</p> +<div class="Bd Pp Li"> +<pre>typedef enum { + FP_PS, /* 24 bit (single-precision) */ + FP_PRS, /* reserved */ + FP_PD, /* 53 bit (double-precision) */ + FP_PE /* 64 bit (extended-precision) */ +} fp_prec_t;</pre> +</div> +<br/> +<var class="Ft">fp_prec_t</var> +<br/> +<code class="Fn">fpgetprec</code>(<var class="Fa" style="white-space: nowrap;">void</var>); +<p class="Pp"><var class="Ft">fp_prec_t</var> + <br/> + <code class="Fn">fpsetprec</code>(<var class="Fa" style="white-space: nowrap;">fp_prec_t + precision</var>);</p> +<div class="Bd Pp Li"> +<pre>#define fp_except_t int +#define FP_X_INV 0x01 /* invalid operation */ +#define FP_X_DNML 0x02 /* denormal */ +#define FP_X_DZ 0x04 /* zero divide */ +#define FP_X_OFL 0x08 /* overflow */ +#define FP_X_UFL 0x10 /* underflow */ +#define FP_X_IMP 0x20 /* (im)precision */ +#define FP_X_STK 0x40 /* stack fault */</pre> +</div> +<br/> +<var class="Ft">fp_except_t</var> +<br/> +<code class="Fn">fpgetmask</code>(<var class="Fa" style="white-space: nowrap;">void</var>); +<p class="Pp"><var class="Ft">fp_except_t</var> + <br/> + <code class="Fn">fpsetmask</code>(<var class="Fa" style="white-space: nowrap;">fp_except_t + mask</var>);</p> +<p class="Pp"><var class="Ft">fp_except_t</var> + <br/> + <code class="Fn">fpgetsticky</code>(<var class="Fa" style="white-space: nowrap;">void</var>);</p> +<p class="Pp"><var class="Ft">fp_except_t</var> + <br/> + <code class="Fn">fpresetsticky</code>(<var class="Fa" style="white-space: nowrap;">fp_except_t + sticky</var>);</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The routines described herein are deprecated. New code should use + the functionality provided by <a class="Xr">fenv(3)</a>.</p> +<p class="Pp">When a floating point exception is detected, the exception sticky + flag is set and the exception mask is tested. If the mask is set, then a + trap occurs. These routines allow both setting the floating point exception + masks, and resetting the exception sticky flags after an exception is + detected. In addition, they allow setting the floating point rounding mode + and precision.</p> +<p class="Pp" id="fpgetround">The + <a class="permalink" href="#fpgetround"><code class="Fn">fpgetround</code></a>() + function returns the current floating point rounding mode.</p> +<p class="Pp" id="fpsetround">The + <a class="permalink" href="#fpsetround"><code class="Fn">fpsetround</code></a>() + function sets the floating point rounding mode and returns the previous + mode.</p> +<p class="Pp" id="fpgetprec">The + <a class="permalink" href="#fpgetprec"><code class="Fn">fpgetprec</code></a>() + function returns the current floating point precision.</p> +<p class="Pp" id="fpsetprec">The + <a class="permalink" href="#fpsetprec"><code class="Fn">fpsetprec</code></a>() + function sets the floating point precision and returns the previous + precision.</p> +<p class="Pp" id="fpgetmask">The + <a class="permalink" href="#fpgetmask"><code class="Fn">fpgetmask</code></a>() + function returns the current floating point exception masks.</p> +<p class="Pp" id="fpsetmask">The + <a class="permalink" href="#fpsetmask"><code class="Fn">fpsetmask</code></a>() + function sets the floating point exception masks and returns the previous + masks.</p> +<p class="Pp" id="fpgetsticky">The + <a class="permalink" href="#fpgetsticky"><code class="Fn">fpgetsticky</code></a>() + function returns the current floating point sticky flags.</p> +<p class="Pp" id="fpresetsticky">The + <a class="permalink" href="#fpresetsticky"><code class="Fn">fpresetsticky</code></a>() + function clears the floating point sticky flags and returns the previous + flags.</p> +<p class="Pp">Sample code which prevents a trap on divide-by-zero:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>fpsetmask(~FP_X_DZ); +a = 1.0; +b = 0; +c = a / b; +fpresetsticky(FP_X_DZ); +fpsetmask(FP_X_DZ);</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="IMPLEMENTATION_NOTES"><a class="permalink" href="#IMPLEMENTATION_NOTES">IMPLEMENTATION + NOTES</a></h1> +<p class="Pp">The <code class="Fn">fpgetprec</code>() and + <code class="Fn">fpsetprec</code>() functions provide functionality + unavailable on many platforms. At present, they are implemented only on the + i386 and amd64 platforms. Changing precision is not a supported feature: it + may be ineffective when code is compiled to take advantage of SSE, and many + library functions and compiler optimizations depend upon the default + precision for correct behavior.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">fenv(3)</a>, <a class="Xr">isnan(3)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">These routines are based on SysV/386 routines of the same + name.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="CAVEATS"><a class="permalink" href="#CAVEATS">CAVEATS</a></h1> +<p class="Pp">After a floating point exception and before a mask is set, the + sticky flags must be reset. If another exception occurs before the sticky + flags are reset, then a wrong exception type may be signaled.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">December 3, 2010</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |