The Open Group Base Specifications Issue 7
IEEE Std 1003.1-2008, 2016 Edition
Copyright © 2001-2016 The IEEE and The Open Group

#### NAME

> fetestexcept - test floating-point exception flags

#### SYNOPSIS

> ``#include <fenv.h>
> int fetestexcept(int` excepts`);
> ``

#### DESCRIPTION

> [CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

> The fetestexcept() function shall determine which of a specified subset of the floating-point exception flags are currently set. The excepts argument specifies the floating-point status flags to be queried.

#### RETURN VALUE

> The fetestexcept() function shall return the value of the bitwise-inclusive OR of the floating-point exception macros corresponding to the currently set floating-point exceptions included in excepts.

#### ERRORS

> No errors are defined.

The following sections are informative.

#### EXAMPLES

> The following example calls function f() if an invalid exception is set, and then function g() if an overflow exception is set:

>     #include <fenv.h>
>     /* ... */
>     {
>         #pragma STDC FENV_ACCESS ON
>         int set_excepts;
>         feclearexcept(FE_INVALID | FE_OVERFLOW);
>         // maybe raise exceptions
>         set_excepts = fetestexcept(FE_INVALID | FE_OVERFLOW);
>         if (set_excepts & FE_INVALID) f();
>         if (set_excepts & FE_OVERFLOW) g();
>         /* ... */
>     }

#### APPLICATION USAGE

> None.

#### RATIONALE

> None.

#### FUTURE DIRECTIONS

> None.

#### SEE ALSO

> feclearexcept, fegetexceptflag, feraiseexcept

> XBD <fenv.h>

#### CHANGE HISTORY

> First released in Issue 6. Derived from the ISO/IEC 9899:1999 standard.

End of informative text.

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