Re: Regex infinite loop?

As you describe it, you say it gets all the matches, and then doesn't move to the next page. That suggests the problem isn't in while($content =~ m%pattern%s). It may be in "Do something". It may be in whatever you using the get the next page. It may be a network problem. It may be a problem on the server you're fetching from. And if you hadn't ruled it out already, it may be that the pattern takes a really long time to determine there's no match.

But I have to say, you give extremely little information. It's just guessing what could be wrong with your program.

Comment on Re: Regex infinite loop?

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Re^2: Regex infinite loop? by Ninth Prince (Acolyte) on Oct 16, 2008 at 18:31 UTC
I understand that I have given you very little to go on. I'm thinking that it's neither a network problem or a server problem because it always hangs on the same page. Even when I change the order in which I retrieve the pages, it still hangs on the same page. So, it seems like the problem is page-specific. I also have a line immediately following my {Do something} block that let's me know that I've exited the match. On the pages where my code hangs, it never exits the {Do something} block. On the time to match part, the match happens fairly quickly whether or not there are zero matches, one match, or multiple matches. One thing I should probably have mentioned, but neglected to, is that I've been running this code for a while now (it runs automatically once a day). Whoever runs the website that I'm pulling from made some minor changes to the HTML, so I needed to go back and change my matching pattern. But, like I said, it matches fine on some web pages, but then hangs on others.	[reply]
Re^3: Regex infinite loop? by moritz (Cardinal) on Oct 16, 2008 at 18:41 UTC
Talk code. Show us the regex, and the data on which it hangs.	[reply]
Re^3: Regex infinite loop? by JavaFan (Canon) on Oct 16, 2008 at 21:27 UTC
But if it "hangs" does it hang in the loop? You've code showing it exits the loop, but do you know it entered the loop? What I would do is first determine where the program "hangs": print a message before fetching a page; print a message after the page was retrieved; print a message before attempting the pattern; print a message when entering the body of the while; print a message just before exiting the body; print a message when exiting the while construct. And to avoid buffer problems, print those messages to STDERR.	[reply]