The
feclearexcept() routine clears the floating-point exception flags specified by
excepts, whereas
feraiseexcept() raises the specified exceptions. Raising an exception causes the corresponding flag to be set, and a
SIGFPE is delivered to the process if the exception is unmasked.
The
fetestexcept() function determines which flags are currently set, of those specified by
excepts.
The
fegetexceptflag() function stores the state of the exception flags specified in
excepts in the opaque object pointed to by
flagp. Similarly,
fesetexceptflag() changes the specified exception flags to reflect the state stored in the object pointed to by
flagp. Note that the flags restored with
fesetexceptflag() must be a (not necessarily proper) subset of the flags recorded by a prior call to
fegetexceptflag().
For all of these functions, the possible types of exceptions include those described in
fenv(3). Some architectures may define other types of floating-point exceptions.