Function dr_unregister_exception_event 

pub unsafe extern "C" fn dr_unregister_exception_event(
    func: Option<unsafe extern "C" fn(drcontext: *mut c_void, excpt: *mut dr_exception_t) -> bool_>,
) -> bool_

Unregister a callback function for the exception event. \return true if unregistration is successful and false if it is not (e.g., \p func was not registered).