fesetenv1.md

title	ms.custom	ms.date	ms.reviewer	ms.suite	ms.technology	ms.tgt_pltfrm	ms.topic	apiname	apilocation	apitype	f1_keywords	dev_langs	helpviewer_keywords	ms.assetid	caps.latest.revision	author	ms.author	manager
fesetenv | Microsoft Docs		11/04/2016			cpp devlang-cpp		article	fesetenv	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-runtime-l1-1-0.dll	DLLExport	fesetenv fenv/fesetenv	C++	fesetenv function	ffc64fff-8ea7-4d59-9e04-ff96ef8cd012	6	corob-msft	corob	ghogen

fesetenv

Sets the current floating-point environment.

Syntax

int fesetenv(  
   const fenv_t *penv  
);  

Parameters

penv
Pointer to a fenv_t object that contains a floating-point environment as set by a call to fegetenv or feholdexcept. You can also specify the default startup floating-point environment by using the FE_DFL_ENV macro.

Return Value

Returns 0 if the environment was successfully set. Otherwise, returns a nonzero value.

Remarks

The fesetenv function sets the current floating-point environment from the value stored in the fenv_t object pointed to by penv. The floating point environment is the set of status flags and control modes that affect floating-point calculations. This includes the rounding mode and the status flags for floating-point exceptions. If penv is not FE_DFL_ENV or does not point to a valid fenv_t object, subsequent behavior is undefined.

A call to this function sets the exception status flags that are in the penv object, but it does not raise those exceptions.

To use this function, you must turn off floating-point optimizations that could prevent access by using the #pragma fenv_access(on) directive prior to the call. For more information, see fenv_access.

Requirements

Function	C header	C++ header
fesetenv	<fenv.h>	<cfenv>

For additional compatibility information, see Compatibility.

See Also

Alphabetical Function Reference
fegetenv
feclearexcept
feholdexcept
fesetexceptflag