FECLEAREXCEPT(3)					   BSD Library Functions Manual 					  FECLEAREXCEPT(3)

NAME

     feclearexcept, fegetexceptflag, feraiseexcept, fesetexceptflag, fetestexcept -- functions providing access to the floating-point status
     flags.

SYNOPSIS

     #include <fenv.h>
     #pragma STDC FENV_ACCESS ON

     int
     feclearexcept(int excepts);

     int
     feraiseexcept(int excepts);

     int
     fetestexcept(int excepts);

     int
     fegetexceptflag(fexcept_t *flagp, int excepts);

     int
     fesetexceptflag(fexcept_t *flagp, int excepts);

DESCRIPTION

     These functions provide access to the floating-point status flags.  The int input argument excepts for the functions represents a subset of
     floating-point exceptions, and can be either zero or the bitwise OR of one or more floating-point exception macros defined in <fenv.h>, for
     example FE_OVERFLOW | FE_INEXACT.	For other argument values the behavior of these functions is undefined.

     The feclearexcept() function attempts to clear the supported floating-point flags corresponding to the exceptions specified by its argument.
     It returns zero if excepts is zero or if the flags corresponding to all specified exceptions were successfully cleared.  Otherwise, it
     returns a nonzero value.

     The feraiseexcept() function attempts to raise the supported floating-point exceptions specified by its argument.	Its effect is similar to
     that of arithmetic operations raising the same exceptions; if traps are enabled for the exceptions that are raised, they will be taken.  The
     order in which these exceptions are raised is unspecified.  On OS X and iOS, raising overflow or underflow using this function will addition-
     ally raise the inexact exception.

     The feraiseexcept() function returns zero if excepts is zero or if the specified exceptions were successfully raised.  Otherwise a nonzero
     value is returned.

     The fetestexcept() function determines if any of the floating-point flags corresponding to the exceptions specified by its argument are cur-
     rently set.  It returns the bitwise OR of the floating-point exception macros corresponding to the currently set flags indicated by excepts.
     For example, if the underflow and inexact flags are set in the floating-point environment, the result of fetestexcept(FE_INEXACT |
     FE_INVALID) will be FE_INEXACT.

     The fegetexceptflag() function attempts to store an implementation-defined representation of the states of the floating-point status flags
     corresponding to the exceptions specified by excepts in the object pointed to by the argument flagp.  It returns zero if the representation
     is successfully stored, and a nonzero value otherwise.

     The fesetexceptflag() function attempts to set the floating-point status flags corresponding to the exceptions specified by excepts to the
     states stored in the object pointed to by flagp.  This function does not raise floating-point exceptions--it only sets the state of the
     flags.  The value of *flagp shall have been set by a previous call to fegetexceptflag() whose second argument represented a superset of the
     exceptions represented by excepts.

     The fesetexceptflag() function returns zero if the excepts argument is zero or if all the specified flags were successfully set.  Otherwise
     it returns a nonzero value.

SEE ALSO

     fenv(3), fegetenv(3), fegetround(3), feholdexcept(3), fesetenv(3), fesetround(3), feupdateenv(3)

STANDARDS

     These functions conform to ISO/IEC 9899:TC3.

OS X
								    May 9, 2011 							      OS X