Interfaces code ignores non-broadcast links

[tridge at samba.org]

Andrew,

 > However, Maurice points out that we don't bind to point-to-point
 > interfaces.

There were two reasons the code avoids non-broadcast interfaces. The
first is (as you guessed) that they aren't needed for our nbt server
doing its browsing stuff. 

The second reason was that we had a problem with on-demand dialup
links. Users complained that Samba was causing their expensive ISDN
links to dial far more often than they should have. These are
generally non-broadcast links so the fix was to avoiding binding to
non-broadcast interfaces.

In Samba4, probably the thing to do is make iface_n_bcast() return
NULL for non-broadcast links, then make all the places that loop over
the list of interfaces check for this, and skip interfaces if they
don't need non-broadcast interfaces.

Cheers, Tridge