SENTINEL_VALUE
assert(win->alines[i]->sentinel == SENTINEL_VALUE);
assert(win->alines[i]->sentinel == SENTINEL_VALUE);
assert(win->alines[i]->sentinel == SENTINEL_VALUE);
lp->sentinel = SENTINEL_VALUE;
lp->sentinel = SENTINEL_VALUE;
lp->sentinel = SENTINEL_VALUE;
lp->sentinel = SENTINEL_VALUE;