As a follow up, you mention the agent string, is there someplace that explains this string in some detail? I just want to understand what is important in that line to different servers.

It's a messy subject. Browsers announce themselves using a "User-Agent:" header in the HTTP request. This is visible to CGIs in the HTTP_USER_AGENT environment variable.

As browsers have developed, they've added capabilities (and have introduced and fixed bugs). There are incompatabilities in things like CSS (Cascading Style Sheet) support between different browsers and browser versions, and even some subtle differences Javascript support.

Some sites use the user-agent string to ensure that they emit the right DHTML/JavaScript from the server side. Also, various JavaScript libraries will include "browser detection" code to run on the client side, so that they can do the right magic stuff (or avoid trying to do the wrong magic stuff) in a browser. A limited number of sites use the user-agent string to be jerks, denying service to one browser type or another "just because."

What the user agent strings are and how to interpret them is scattered throughout the available literature. Try googling on "Javascript browser detect".

In reply to Re: Re: Re: Why don't I get a redirect by dws
in thread Why don't I get a redirect by jonjacobmoon

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