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FETESTEXCEPT 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
fetestexcept - test floating-point exception flags

c99 [ flag... ] file... -lm [ library... ]
#include <fenv.h>

int fetestexcept(int excepts);

The fetestexcept() function determines 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.


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


No errors are defined.


Example 1 Example using fetestexcept()

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>
/* ... */
 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();
 /* ... */

See attributes(5) for descriptions of the following attributes:

Interface Stability Standard
MT-Level MT-Safe

feclearexcept(3M), fegetexceptflag(3M), fenv.h(3HEAD), attributes(5), standards(5)