WIN_INIT
if (init > WIN_INIT)
init = WIN_INIT;
else if (s->high_water < (ulg)curr + WIN_INIT) {
init = (ulg)curr + WIN_INIT - s->high_water;
if (init > WIN_INIT)
init = WIN_INIT;
else if (s->high_water < (ulg)curr + WIN_INIT) {
init = (ulg)curr + WIN_INIT - s->high_water;