- while (n && !feof(f)) {
- z = memchr(f->rpos, '\n', f->rend - f->rpos);
- k = z ? z - f->rpos + 1 : f->rend - f->rpos;
- k = MIN(k, n);
- memcpy(p, f->rpos, k);
- f->rpos += k;
- p += k;
- n -= k;
- if (z) break;
- __underflow(f);
+ if (n--<=1) {
+ f->mode |= f->mode-1;
+ FUNLOCK(f);
+ if (n) return 0;
+ *s = 0;
+ return s;
+ }
+
+ while (n) {
+ if (f->rpos != f->rend) {
+ z = memchr(f->rpos, '\n', f->rend - f->rpos);
+ k = z ? z - f->rpos + 1 : f->rend - f->rpos;
+ k = MIN(k, n);
+ memcpy(p, f->rpos, k);
+ f->rpos += k;
+ p += k;
+ n -= k;
+ if (z || !n) break;
+ }
+ if ((c = getc_unlocked(f)) < 0) {
+ if (p==s || !feof(f)) s = 0;
+ break;
+ }
+ n--;
+ if ((*p++ = c) == '\n') break;