o Don't try to transfer tty device descriptors as there's no way of

o Don't try to transfer tty device descriptors as there's no way of
  transferring session rights with them.  Instead, create two
  `/bin/cat' processes.  A new child is spawned and disassociated from
  the terminal and the parent, which continues with the rest of the ppp
  process.  Meanwhile, the parent spawns another child, and both the
  parent and child exec the `/bin/cat' commands with the appropriate
  descriptors.  This way, the session is owned by the parent, and the
  tty is held open.
o Close LCPs that have done a TLF and are now in ST_STOPPED before
  calling Down.  This prevents them from trying to come back up again
  after the peer has shut them down (it seems a bit strange that the
  rfc says that a Down in ST_STOPPED will cause a TLS etc).
o Don't try to set the physical link name pointer when we're receiving
  and renaming a datalink.  The physical hasn't been created yet, and as
  it happens, the garbage physical pointer happens to be the value of another
  physical - so we're pointing that other physical name at ourselves.
  yeuck.
o Re-arrange the order of things in main (DoLoop()).  We now handle
  signals only after the select and not before the UpdateSet.  It's
  possible that either a signal (FSM timeout) or a descriptor_Read()
  brings a link down, after which we'd better tidy up any dead direct
  and 1off descriptors before calling UpdateSet() again.
o Mention when we detect a PPP packet when we see one before the link
  is up (then start LCP as before).