2130706433 is not a valid IP address as most people think of them.

Likewise, "login=juerd" is not a valid cookie as most people think of them. They expect them to be edible. What most people think and what is technically correct isn't always the same.

The Unix inet_ntoa accepts all kinds of non-standard forms for IP addresses.

Yes, like the ones formed like "127.0.0.1". This is only a de-facto standard, not an official one. It happens to be accepted by almost everything that takes an IP address. Decimal numbers like "2130706433" are also a de-facto standard; they are just not used as much. The libraries found in Unix, Linux, Windows and Mac OS all think "2130706433" and "127.0.0.1" are the same address.

Everyone else thinks that IP addresses are represented as four decimal numbers sepated by periods. Using anything else will confuse people and programs that expect the standard form.

We could argue about the meaning of "everyone else" or about "anything else", or even about who you think "people" are. Or we could just stick to your point and discuss the "standard" status of dotted decimal IP addresses. That some applications and even some protocols require IP addresses to be stringified like that does not mean that it is the only standard - or that it even is a standard.

Should you have an STD, RFC or another official document that says more on this subject, I'll be happy to hear about it.

Juerd # { site => 'juerd.nl', plp_site => 'plp.juerd.nl', do_not_use => 'spamtrap' }

In reply to Re: Re: Re: Untaint IP address/hostname question by Juerd
in thread Untaint IP address/hostname question by jcpunk

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