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http - Easy way to test a URL for 404 in PHP?

I'm teaching myself some basic scraping and I've found that sometimes the URL's that I feed into my code return 404, which gums up all the rest of my code.

So I need a test at the top of the code to check if the URL returns 404 or not.

This would seem like a pretty straightfoward task, but Google's not giving me any answers. I worry I'm searching for the wrong stuff.

One blog recommended I use this:

$valid = @fsockopen($url, 80, $errno, $errstr, 30);

and then test to see if $valid if empty or not.

But I think the URL that's giving me problems has a redirect on it, so $valid is coming up empty for all values. Or perhaps I'm doing something else wrong.

I've also looked into a "head request" but I've yet to find any actual code examples I can play with or try out.

Suggestions? And what's this about curl?

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If you are using PHP's curl bindings, you can check the error code using curl_getinfo as such:

$handle = curl_init($url);
curl_setopt($handle,  CURLOPT_RETURNTRANSFER, TRUE);

/* Get the HTML or whatever is linked in $url. */
$response = curl_exec($handle);

/* Check for 404 (file not found). */
$httpCode = curl_getinfo($handle, CURLINFO_HTTP_CODE);
if($httpCode == 404) {
    /* Handle 404 here. */
}

curl_close($handle);

/* Handle $response here. */

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