This is a valid ipv4 address

Re:This is a valid ipv4 address by ClashTheBunny on Monday October 21, 2013 @03:47AM (#6583985)

This is not true. 0.0.0.0 may end up at localhost for you, but it's not localhost. I just get: PING 0.0.0.0 (0.0.0.0): 56 data bytes ping: sendto: No route to host

Which system do you use that this works on?

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Re:This is a valid ipv4 address by reidrac on Monday October 21, 2013 @05:35AM (#6584383)

I don't know about the OP, but in Ubuntu Precise "ping 0" pings to 127.0.0.1.

I can't explain why.

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Re:This is a valid ipv4 address by ordinary on Monday October 21, 2013 @06:45AM (#6584580)

From what I can tell, the use of '0' or '0.0.0.0' as a destination address is not official. It should only be used as a source address. From RFC 5735 - Special USe IPv4 Addresses:

   0.0.0.0/8 - Addresses in this block refer to source hosts on "this"
   network.  Address 0.0.0.0/32 may be used as a source address for this
   host on this network; other addresses within 0.0.0.0/8 may be used to
   refer to specified hosts on this network.

Support for it looks to be flaky. 'ping 0' and 'ping 0.0.0.0' work for me on various Linuxes ("64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.026 ms"), but not on Windows 7 ("sendto: Cannot assign requested address") or Windows Server 2003 ("Destination specified is invalid").

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Re:This is a valid ipv4 address by reidrac on Monday October 21, 2013 @07:11AM (#6584667)

IPv6 behaviour seems to be the same: "ping6 ::" pings to ::1: (localhost).

This is intriguing, really :)

EDIT: oh, you already pointed to the RFC :)

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