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diff --git a/devdocs/c/numeric%2Ffenv%2Ffe_dfl_env.html b/devdocs/c/numeric%2Ffenv%2Ffe_dfl_env.html deleted file mode 100644 index bbc17453..00000000 --- a/devdocs/c/numeric%2Ffenv%2Ffe_dfl_env.html +++ /dev/null @@ -1,80 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">FE_DFL_ENV</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><fenv.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">#define FE_DFL_ENV /*implementation defined*/</pre> -</td> <td class="t-dcl-nopad"> </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> </table> <p>The macro constant <code>FE_DFL_ENV</code> expands to an expression of type <code>const fenv_t*</code>, which points to a full copy of the default floating-point environment, that is, the environment as loaded at program startup.</p> -<p>Additional macros that begin with <code>FE_</code> followed by uppercase letters, and have the type <code>const fenv_t*</code>, may be supported by an implementation.</p> -<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h> -#include <fenv.h> - -#pragma STDC FENV_ACCESS ON - -void show_fe_exceptions(void) -{ - printf("current exceptions raised: "); - if(fetestexcept(FE_DIVBYZERO)) printf(" FE_DIVBYZERO"); - if(fetestexcept(FE_INEXACT)) printf(" FE_INEXACT"); - if(fetestexcept(FE_INVALID)) printf(" FE_INVALID"); - if(fetestexcept(FE_OVERFLOW)) printf(" FE_OVERFLOW"); - if(fetestexcept(FE_UNDERFLOW)) printf(" FE_UNDERFLOW"); - if(fetestexcept(FE_ALL_EXCEPT)==0) printf(" none"); - printf("\n"); -} - -void show_fe_rounding_method(void) -{ - printf("current rounding method: "); - switch (fegetround()) { - case FE_TONEAREST: printf ("FE_TONEAREST"); break; - case FE_DOWNWARD: printf ("FE_DOWNWARD"); break; - case FE_UPWARD: printf ("FE_UPWARD"); break; - case FE_TOWARDZERO: printf ("FE_TOWARDZERO"); break; - default: printf ("unknown"); - }; - printf("\n"); -} - -void show_fe_environment(void) -{ - show_fe_exceptions(); - show_fe_rounding_method(); -} - -int main() -{ - printf("On startup:\n"); - show_fe_environment(); - - // Change environment - fesetround(FE_DOWNWARD); // change rounding mode - feraiseexcept(FE_INVALID); // raise exception - printf("\nBefore restoration:\n"); - show_fe_environment(); - - fesetenv(FE_DFL_ENV); // restore - printf("\nAfter restoring default environment:\n"); - show_fe_environment(); -}</pre></div> <p>Output:</p> -<div class="text source-text"><pre data-language="c">On startup: -current exceptions raised: none -current rounding method: FE_TONEAREST - -Before restoration: -current exceptions raised: FE_INVALID -current rounding method: FE_DOWNWARD - -After restoring default environment: -current exceptions raised: none -current rounding method: FE_TONEAREST</pre></div> </div> <h3 id="References"> References</h3> <ul> -<li> C11 standard (ISO/IEC 9899:2011): </li> -<ul><li> 7.6/9 Floating-point environment <fenv.h> (p: 208) </li></ul> -<li> C99 standard (ISO/IEC 9899:1999): </li> -<ul><li> 7.6/8 Floating-point environment <fenv.h> (p: 188-189) </li></ul> -</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="feenv" title="c/numeric/fenv/feenv"> <span class="t-lines"><span>fegetenv</span><span>fesetenv</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> saves or restores the current floating-point environment <br> <span class="t-mark">(function)</span> </td> -</tr> <tr class="t-dsc"> <td> <div><a href="feupdateenv" title="c/numeric/fenv/feupdateenv"> <span class="t-lines"><span>feupdateenv</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> restores the floating-point environment and raises the previously raise exceptions <br> <span class="t-mark">(function)</span> </td> -</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/numeric/fenv/FE_DFL_ENV" title="cpp/numeric/fenv/FE DFL ENV">C++ documentation</a></span> for <code>FE_DFL_ENV</code> </td> -</tr> </table> <div class="_attribution"> - <p class="_attribution-p"> - © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> - <a href="https://en.cppreference.com/w/c/numeric/fenv/FE_DFL_ENV" class="_attribution-link">https://en.cppreference.com/w/c/numeric/fenv/FE_DFL_ENV</a> - </p> -</div> |