To identify existing pages and to avoid invalid pages

I have to identify whether a particular url is existing or not. For that, using curl i can retrieve the contents of the page. If a particular domain is not an existing one, then I can obtain the error msg "Couldn't resolve host '' " and corresponding error code using curl, so that i can trace it properly. But if a domain exist, and there will be a common error page for showing pages which are not found, the curl will give the contents in the corresponding error page, and will treat it as an existing page. There will not be any error message or error code in this case. So how can I identify properly whether the particular link inside an existing domain is an existing link or not....
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Dave BaldwinFixer of ProblemsCommented:
There in no guarateed way.  You could use 'CURLINFO_HTTP_CODE - Last received HTTP code ' in "curl_getinfo()" to see if you received a "404 - page not found" error code.  However that only works on 'well-behaved' sites.  Some sites redirect you to a page that returns a '200 - Ok' code.  On those you have no way of telling.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.