EL_LEAVE
el->el_line.limit = &el->el_line.buffer[EL_BUFSIZ - EL_LEAVE];
sz = el->el_line.limit - el->el_line.buffer + EL_LEAVE;
el->el_line.limit = &newbuffer[sz - EL_LEAVE];
el->el_line.limit = &el->el_line.buffer[newsz - EL_LEAVE];