Hi,
    Is there any standard way to determine whether a particular
address is IPV6 or not?I need to find find the address which i am
getting is IPV6 in my code and also whether it is valid IP?please give
me suggestions :-)

wrote in message 
news:ef75c65f-14dc-4892-8b1e-6021c93a29d0@y22g2000prd.googlegroups.com...
>    Is there any standard way to determine whether a particular
> address is IPV6 or not?I need to find find the address which i am
> getting is IPV6 in my code and also whether it is valid IP?please give
> me suggestions :-)

If it's a string you're getting, an IPv6 numerical address will contain hex 
digits and colons (with the possibility of a percent character).

If it's a binary structure, you'll find the address family member tells you 
what address family (AF_INET or AF_INET6) the address is in.

If it's a name, you have to ask the DNS - request DNS records for all the 
address families you support, and then proceed through the results in 
decreasing order of your preference until you find one that connects.

Alun.
~~~~
-- 
Texas Imperial Software   | Web: http://www.wftpd.com/
23921 57th Ave SE         | Blog: http://msmvps.com/alunj/
Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
Fax/Voice +1(425)807-1787 | Try our NEW client software, WFTPD Explorer.

On May 16, 7:57 pm, "Alun Jones" <a...@texis.invalid> wrote:
>  wrote in message
>
> news:ef75c65f-14dc-4892-8b1e-6021c93a29d0@y22g2000prd.googlegroups.com...
>
> >    Is there any standard way to determine whether a particular
> > address is IPV6 or not?I need to find find the address which i am
> > getting is IPV6 in my code and also whether it is valid IP?please give
> > me suggestions :-)
>
> If it's a string you're getting, an IPv6 numerical address will contain hex
> digits and colons (with the possibility of a percent character).
>
> If it's a binary structure, you'll find the address family member tells you
> what address family (AF_INET or AF_INET6) the address is in.
>
> If it's a name, you have to ask the DNS - request DNS records for all the
> address families you support, and then proceed through the results in
> decreasing order of your preference until you find one that connects.
>
> Alun.
> ~~~~
> --
> Texas Imperial Software   | Web:http://www.wftpd.com/
> 23921 57th Ave SE         | Blog:http://msmvps.com/alunj/
> Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
> Fax/Voice (425)807-1787 | Try our NEW client software, WFTPD Explorer.

Hi Alun,
             Is there any API to test particular address is IPV6 or
not,or any algoritham is there to determine the address is IPV6.IPV6
address can also be expressed with '-' this makes conflict with
NetBIOS name so while coding this makes difficult me to differentiate
between IPV6 and NetBIOS name..

wrote in message 
news:158f5bff-d963-4518-aead-ffe6c148816d@s33g2000pri.googlegroups.com...
>             Is there any API to test particular address is IPV6 or
> not,or any algoritham is there to determine the address is IPV6.IPV6
> address can also be expressed with '-' this makes conflict with
> NetBIOS name so while coding this makes difficult me to differentiate
> between IPV6 and NetBIOS name..

Perhaps you could demonstrate the kind of 'address' you're confused about.

If you're looking at numeric addresses, there is no such confusion - an IPv4 
address is four groups of decimal digits, separated by dots; an IPv6 address 
is hexadecimal digits separated by colons, with a single long string of 
hexadecimal zeroes replaced by "::".

If you're looking at names, you have to query for all addresses that are of 
a type you can handle.

Alun.
~~~~
-- 
Texas Imperial Software   | Web: http://www.wftpd.com/
23921 57th Ave SE         | Blog: http://msmvps.com/alunj/
Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
Fax/Voice +1(425)807-1787 | Try our NEW client software, WFTPD Explorer.

On May 26, 8:46 am, "Alun Jones" <a...@texis.invalid> wrote:
>  wrote in message
>
> news:158f5bff-d963-4518-aead-ffe6c148816d@s33g2000pri.googlegroups.com...
>
> >             Is there any API to test particular address is IPV6 or
> > not,or any algoritham is there to determine the address is IPV6.IPV6
> > address can also be expressed with '-' this makes conflict with
> > NetBIOS name so while coding this makes difficult me to differentiate
> > between IPV6 and NetBIOS name..
>
> Perhaps you could demonstrate the kind of 'address' you're confused about.> If you're looking at numeric addresses, there is no such confusion - an IPv4
> address is four groups of decimal digits, separated by dots; an IPv6 address
> is hexadecimal digits separated by colons, with a single long string of
> hexadecimal zeroes replaced by "::".
>
> If you're looking at names, you have to query for all addresses that are of
> a type you can handle.
>
> Alun.
> ~~~~
> --
> Texas Imperial Software   | Web:http://www.wftpd.com/
> 23921 57th Ave SE         | Blog:http://msmvps.com/alunj/
> Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
> Fax/Voice (425)807-1787 | Try our NEW client software, WFTPD Explorer.

Hi Alun,
           Thank you so much for your help but I have some doubts,such
as IPV6 address can be represented by removing the zeros which comes
in between so is it possible to confirm whether it is IPV6 by
observing the four hexa decimal part?actually i need to write code to
verify  whether it is IPV6,so if by mistake i conclude as IPV6 that
will go on resolving IPV6 address.If it is not IPV6 it will impact in
NetBIOS,The second solution you mentioned about name I didnt get,
query for all addresses that are of a type you can handle,How can I do
that?Once again I express my thanks,I welcome your valuble
suggestions.

regards,
Arun.

wrote in message 
news:ffae2783-fa32-4429-b7a0-72c5ed8da4c0@u36g2000prf.googlegroups.com...
>           Thank you so much for your help but I have some doubts,such
> as IPV6 address can be represented by removing the zeros which comes
> in between so is it possible to confirm whether it is IPV6 by
> observing the four hexa decimal part?actually i need to write code to
> verify  whether it is IPV6,so if by mistake i conclude as IPV6 that
> will go on resolving IPV6 address.If it is not IPV6 it will impact in
> NetBIOS,The second solution you mentioned about name I didnt get,
> query for all addresses that are of a type you can handle,How can I do
> that?Once again I express my thanks,I welcome your valuble
> suggestions.

IPv6 addresses don't start with ::, but there is a possibility that they 
will start with some smaller sequence than four hex digits.

Why not use the operating system to your advantage?

Most software that takes an input that it treats as a site to connect to 
will use getaddrinfo to determine whether the address is a name or numeric 
address, which protocol it is, and to resolve names if it is indeed a name.

Then you only have to know that if there is a possibility of a port being 
supplied, it will be in one of the following forms:

name.example.com:80
198.162.0.2:80
[2001:db8::10fe:42a3:1]:80

It should not be difficult to determine whether you have one of these forms.

Alun.
~~~~
-- 
Texas Imperial Software   | Web: http://www.wftpd.com/
23921 57th Ave SE         | Blog: http://msmvps.com/alunj/
Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
Fax/Voice +1(425)807-1787 | Try our NEW client software, WFTPD Explorer.

Alun Jones wrote:
> IPv6 addresses don't start with ::, but there is a possibility that they 
> will start with some smaller sequence than four hex digits.
IPv6 addresses can start with ::. Localhost is ::1 in IPv6. :: is 
address itself.

> Most software that takes an input that it treats as a site to connect to 
> will use getaddrinfo to determine whether the address is a name or 
> numeric address, which protocol it is, and to resolve names if it is 
> indeed a name.
That's good advice.

Regards,
Dalius

"Dalius Dobravolskas"  wrote in message 
news:#KoxWiUwIHA.5832@TK2MSFTNGP02.phx.gbl...
> Alun Jones wrote:
>> IPv6 addresses don't start with ::, but there is a possibility that they 
>> will start with some smaller sequence than four hex digits.
> IPv6 addresses can start with ::. Localhost is ::1 in IPv6. :: is address 
> itself.

Thanks for the correction.

Again, that's why you shouldn't rely on some shoddy advice on what is or 
isn't a good address - you should pass it off to an OS component to validate 
it for you.  getaddrinfo, for instance, will let you know that "::" is not a 
good address to connect to, but will work for a listening socket.

Alun.
~~~~
-- 
Texas Imperial Software   | Web: http://www.wftpd.com/
23921 57th Ave SE         | Blog: http://msmvps.com/alunj/
Woodinville WA 98072-8661 | WFTPD, WFTPD Pro are Windows FTP servers.
Fax/Voice +1(425)807-1787 | Try our NEW client software, WFTPD Explorer.

"Alun Jones" <alun@texis.invalid> wrote in message
news:567A3156-1015-4C8C-B645-CA703CFB96ED@microsoft.com...
>  wrote in message
> news:ffae2783-fa32-4429-b7a0-72c5ed8da4c0@u36g2000prf.googlegroups.com...
> >           Thank you so much for your help but I have some doubts,such
> > as IPV6 address can be represented by removing the zeros which comes
> > in between so is it possible to confirm whether it is IPV6 by
> > observing the four hexa decimal part?actually i need to write code to
> > verify  whether it is IPV6,so if by mistake i conclude as IPV6 that
> > will go on resolving IPV6 address.If it is not IPV6 it will impact in
> > NetBIOS,The second solution you mentioned about name I didnt get,
> > query for all addresses that are of a type you can handle,How can I do
> > that?Once again I express my thanks,I welcome your valuble
> > suggestions.
>
> IPv6 addresses don't start with ::, but there is a possibility that they
> will start with some smaller sequence than four hex digits.

IPv6 addresses CAN start with ::.  Currently, we don't have any purely
native addresses that do.  Only the IPv4-mapped and the depreciated
IPv4-compatible ones do, but that doesn't rule out future assignments.

> ...

IPv6 address literal characteristics:

Have only characters [0-9a-fA-F:.].  Any other non-alphabetic terminates the
string (i.e. separators for other things, like "%" for interface).
Have at least 2 and no more than 7 colons.
Have zero or 3 periods (certain special addresses only - IPv4 mappings),
trailing all colons.  With periods present, no more than 6 colons.
Have a length of 2 to 39 characters.
Between each colon, and before the first, has 0-4 alphanumeric characters.
A doubled colon ("::") may appear only once.

That's not a complete specification, but that should get you started.

On May 31, 6:59 am, "D. Stussy"  wrote:
> "Alun Jones" <a...@texis.invalid> wrote in message
>
> news:567A3156-1015-4C8C-B645-CA703CFB96ED@microsoft.com...
>
> >  wrote in message
> >news:ffae2783-fa32-4429-b7a0-72c5ed8da4c0@u36g2000prf.googlegroups.com...> > >           Thank you so much for your help but I have some doubts,such
> > > as IPV6 address can be represented by removing the zeros which comes
> > > in between so is it possible to confirm whether it is IPV6 by
> > > observing the four hexa decimal part?actually i need to write code to
> > > verify  whether it is IPV6,so if by mistake i conclude as IPV6 that
> > > will go on resolving IPV6 address.If it is not IPV6 it will impact in
> > > NetBIOS,The second solution you mentioned about name I didnt get,
> > > query for all addresses that are of a type you can handle,How can I do> > > that?Once again I express my thanks,I welcome your valuble
> > > suggestions.
>
> > IPv6 addresses don't start with ::, but there is a possibility that they> > will start with some smaller sequence than four hex digits.
>
> IPv6 addresses CAN start with ::.  Currently, we don't have any purely
> native addresses that do.  Only the IPv4-mapped and the depreciated
> IPv4-compatible ones do, but that doesn't rule out future assignments.
>
> > ...
>
> IPv6 address literal characteristics:
>
> Have only characters [0-9a-fA-F:.].  Any other non-alphabetic terminates the
> string (i.e. separators for other things, like "%" for interface).
> Have at least 2 and no more than 7 colons.
> Have zero or 3 periods (certain special addresses only - IPv4 mappings),
> trailing all colons.  With periods present, no more than 6 colons.
> Have a length of 2 to 39 characters.
> Between each colon, and before the first, has 0-4 alphanumeric characters.> A doubled colon ("::") may appear only once.
>
> That's not a complete specification, but that should get you started.

Thank you all, for all valuble suggestions :-)