This is all a matter of context - The IP address of 0.0.0.0 is indeed valid if dealing with network routes.

Furthermore, the aspect of leading zeros is also contextual as an IP address is a 32-bit binary number, the dotted-quad merely a representation of this - It could be rightly argued that the leading zeros are nothing more than another representation of an IP address.

See ybiC's Don't Use Regular Expressions To Parse IP Addresses! for an excellent treatise on this topic.

 

perl -le 'print+unpack("N",pack("B32","00000000000000000000001000000111"))'

In reply to Re: Re: Re: Re: IP Address Sanity by rob_au
in thread IP Address Sanity by Anonymous Monk

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