Creating a dynamic redirect in PHP

I'm not sure what the right term is, but I've created hundreds of "redirect:" pages that are place holders for content not created. These pages are created by programming, [and each one redirects to a different place] but they are uploaded as static pages.

They are pages with

<META HTTP-EQUIV="Refresh" CONTENT="5; URL=http:.......

Now what I want to do is replace my custom 404 not found page for the site, with a PHP page, that will somehow pick up the URL string that the browser tried to go to, and dynamically decide what page it should go to, and create the redirect on the fly.

Now I keep meaning to learn PHP, so I might as well start someplace. I've no idea how I find what the original target URL was.

My concern is that if I by mistake I redirect to another page not found, then I could get caught in an endless loop.

 

What kind of 404's are you getting? With some examples it might be easy to see how you could dynamically redirect them to a static url.

Btw, $_SERVER["REQUEST_URI"] should tell you what you are looking for to start with, I think. Not a PHP expert but it's not extremely difficult.

 

I did a quick test, and that looks like what I need to get me started. Off to read about how to parse strings in PHP. Thanks.

 

OK, I got it working - I think. I'm just waiting for my Host to reset the default 404 page to my new PHP page.