Non-polling dynamic DNS utility for linux.
dyndns is a utility for linux that will listen for IP address changes on an interface, and display them
or use them to fetch a website.
The only requirement is libcurl.
dyndns [-v] [-46] [--allow-private] <interface> [URL]
If called with one option, dyndns will print new IP addresses to stdout.
If called with two it will GET the address specified by URL, substituting the pattern <ipaddr>
for the new IP address. The pattern may occur zero or more times.
If neither -4 nor -6 is specified, it will listen for both IPv4 and IPv6 addresses, otherwise it will
react only to the specified one. Both may be explicitly specified.
If --allow-private is specified, it will also react to private IPv4 addresses (10.0.0.0/8, 172.16.0.0/12,
192.168.0.0/16) and IPv6 Unique Local Addresses (fc00::/7), otherwise these will be ignored.
-v adds some additional verbosity, but doesn't really do much.