Is there any documentation for omitting zeroes in dot-decimal notation of IPv4 addresses?

Question

I’ve noticed that Linux and *BSD systems allow user to skip octets when using dot-decimal notation. Here are some examples: ``` $ ping 10.1 PING 10.1 (10.0.0.1) 56(84) bytes of data. $ ping 10.15.1 PING 10.15.1 (10.15.0.1) 56(84) bytes of data. ``` Note that this isn’t limited to the ping command. I’ve found document defining textual representations of IPv4, but it doesn’t seem to cover that feature: Textual Representation of IPv4 and IPv6 Addresses. Is there any other document defining this behavior? Is there a specific name for this behavior?

Accepted Answer

See `inet_aton()` man page. The last part is the numerical value representing the contents of the remaining bits in the address, i.e., a 24-bit `y` in `x.y`, and a 16-bit `z` in `x.y.z`.

Is there any documentation for omitting zeroes in dot-decimal notation of IPv4 addresses?

Solution

Problem