Problems With Ifconfig(8) in 4.2BSD

[jdd at allegra.UUCP]

The ifconfig(8) program, used to configure network devices in 4.2BSD, has a
couple of cute features relating to ARP.

First, the meanings of the "arp" and "-arp" flags are reversed in the
program from their definitions in the manual page.  Specifying "arp" turns
ARP off; specifying "-arp" turns it on.

Second, when ifconfig(8) reports the configuration, it does not interpret
the IFF_NOARP bit, so it doesn't tell you whether or not ARP is on.  The
user must know that 0x80 means IFF_NOARP.

Cheers,
John ("I Hate ARP") DeTreville
Bell Labs, Murray Hill