Re: How to determine if IPv6 is installed (using VC++ 6.0)

From: Eugene Gershnik (gershnik_at_hotmail.com)
Date: 01/05/05 

Date: Wed, 5 Jan 2005 13:21:37 -0800

Alun Jones [MSFT] wrote:
> Usually, though, the best way of determining if a resource is
> available is to try and use it, and handle the failure response. You'd
> hate to come up with some grandiose scheme to tell if IPv6 is
> installed, and find that your app puts up a dialog box saying "IPv6
> is not installed", when other apps are happily using it, because they
> don't bother to check that way, and simply open and use IPv6 sockets!

That depends. If an application was only tested on a few specific
configurations (and most application are) which can be detected in a certain
way than it is better to try to detect them and at least warn the user. A
better message would be "App X cannot detect a supported version of IPv6. Do
you want to try to connect anyway? WARNING: using an unsupported version of
IPv6 may or may not work yada, yada"
You win two psychological victories this way. First if something doesn't
work the user would at least have some clue and hate your app a little less.
Second if he contacts support he may remeber to mention this message which
would simplify your life immensly. 

--
Eugene

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