Note that the PHY is still half-duplex, but we don't need to insist
on the entire packet reception/transmission to finish before letting
the peer have its say.
- dirtpan.c (open_tun): if a command is given, set the environment
variable ITF to the interface name and system(3) the command
- dirtpan.c (usage, main): accept an interface configuration command as
the 4th command-line argument
Note that we still waste at least one perfectly good frame. However,
instead of implementing some fancy arbitration, it's better if we
just make the whole thing bidirectional in the future.
The IEEE 802.15.4 kernel stack doesn't implement ACKs yet and prints
a warning if we request them. Since dirtpan has its own ACKs, we
just disable IEEE 802.15.4 ACKs for now.
- dirtpan.c (debug_ip): only dump local packets if debug > 1
- dirtpan.c (debug_dirt): dump packet content only if debug > 1
- dirtpan.c (debug_dirt): made packet content dump more readable
- dirtpan.c (debug_dirt): added terse debug output for debug == 1
- dirtpan.c (usage): doubling -d now has a meaning
