KBLOCK
if ((unsigned)(ksize + KBLOCK) <= (unsigned)ksize) {
if ((nbufp = malloc((unsigned)(ksize + KBLOCK))) == NULL) {
ewprintf("Can't get %ld bytes", (long)(ksize + KBLOCK));
nstart = (dir == KBACK) ? (kstart + KBLOCK) : (KBLOCK / 4);
ksize += KBLOCK;