io.c:1358
static void
rb_io_fptr_cleanup(fptr, noraise)
    OpenFile *fptr;
    int noraise;
{
    if (fptr->finalize) {
	(*fptr->finalize)(fptr, noraise);
    }
    else {
	fptr_finalize(fptr, noraise);
    }

    if (fptr->path) {
	free(fptr->path);
	fptr->path = 0;
    }
}
