set_unblock_function   96 thread.c       static void set_unblock_function(rb_thread_t *th, rb_unblock_function_t *func, void *arg,
set_unblock_function  958 thread.c           set_unblock_function(th, func, arg, &region->oldubf);
set_unblock_function 3043 thread.c       	    set_unblock_function(th, lock_interrupt, mutex, &oldubf);