- Implement a reference counter to ensure that newly entered records are not
  purged immediately (really needed?)
- Perhaps do a two-step form of recursive query: first query those servers we
  have got cached, then (if unsuccessful) look the others up and query again.
  The impact of this optimisation may not be very big, because all sane servers
  give A records for NS records if possible.
- Test for compatibility on other Unix-like Systems other than the BSDs and
  Linux; rewrite the functions in netdev.c and icmp.c for those OSs if
  necessary. Also try to get compatibility for other compilers than gcc.
- Write an install rule for the Slackware start-up script.
- Update the FAQ.
