I've created some WordPress plugins using cURL for file access. One of the users, however, is having an issue.

Now, my program checks if the cURL extensions are installed first and only proceeds if they are - in the case of this user they are. However, the first curl command which is curl_init() is returning nothing - it should return a handle for the other cURL commands to use.

Unfortunately, I can't find a way to find out what is causing this problem - all the cURL commands for error reporting require the handle.

Does anybody know why this could be happening?

David.

Is it returning nothing, or false ?
http://www.php.net/manual/en/function.curl-init.php

Return Values

Returns a cURL handle on success, FALSE on errors.

straight from the php manual:
http://www.php.net/manual/en/function.curl-error.php

PHP Code:

  <?php
// Create a curl handle to a non-existing location
$ch = curl_init('http://404.php.net/');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

if(curl_exec($ch) === false)
{
    echo 'Curl error: ' . curl_error($ch);
}
else
{
    echo 'Operation completed without any errors';
}

// Close handle
curl_close($ch);
?>

Sorry, it's returning False.

The thing is, the cURL commands to output those errors require a handle - and, naturally, I don't have one because the INIT has failed. Any suggestions on how I find out why this has failed?

David.

Look at my post, and try to use the second function, from which came the snippet to identify where your problem is.
The hint is "curl_error()".

But will that work? curl_error is dependant on a valid handle being used -as none was returned from the INIT, will this actually generate an error? I would have thought that, looking at your code, this would be used to report on any errors from the curl_setopt?

No, my mistake - it's not returning false. When I output the content it's blank.

So if I run this (where $filein contains the file name)...

PHP Code:

if (in_array('curl',get_loaded_extensions())===true) {
    $cURL = curl_init($filein);
    if ($cURL!==false) {
        echo "<p>Result of successful curl_init: ".$cURL."</p>"; 
    } else {
        echo "<p>Curl error:".curl_error($cURL)."</p>";
    }
} 


..I get a success. If my user runs it, it still says the curl_init was successful but no handle is output.

David.

Ok, so going further, does the $ch returned after the init is really a curl resource?
You can check that with

PHP Code:

if (in_array('curl',get_loaded_extensions())===true) {
    $cURL = curl_init($filein);
    var_dump($ch);   //should output something like "resource(4) of type (curl)"
    if ($cURL!==false) {
        echo "<p>Result of successful curl_init: ".$cURL."</p>"; 
    } else {
        echo "<p>Curl error:".curl_error($cURL)."</p>";
    }
} 


Another thing, what is the content of $filein ?

Do you mean $cURL rather than $ch (in my example)? Assuming so, I guess you're wondering whether it's already in use - maybe this will explain the difference between the code working for me and not my user - maybe his WordPress installation is using $cURL as a resource already??

I'll try it and report back.

David.

Do you mean $cURL rather than $ch (in my example)

My bad...
Yes, it's what I meant. I was looking at the code of the snippet at that moment.

I guess you're wondering whether it's already in use

Not necessarily, but it would be good to check.
But I don't think so, as the last call assigning a value to $cURL will replace the preceding value.

My question was more, in this line

PHP Code:

$cURL = curl_init($filein); 


What is the value fo $filein ?
The error might be there...

There might be cases where the content of that value can make curl to bail out.
Like the curl_init comment says:

Be careful when using spaces in the URL... make sure to replace them with + signs, otherwise it won't work.

For some reason on some webservers it may not be able to understand what cURL is doing. If you're getting unexpected results (like getting no output when the URL is valid) while using curl_init(). Add a trailing slash '/' after the url if you haven't done so already.

The content of $filein is...

http://bit.ly/api?url=http%3A%2F%2Fw...bove-rizoto%2F

As you can see, no spaces. This content works for me but not my user.

I've checked the return from the curl_init and it is NOT returning false, but instead blanks.

Any further thoughts on what this could be?

David.

Do you happen to know which version of PHP is installed on your user server ?
Maybe the problem is there, because if it works on your machine, like it does on my server, the problem is located somewhere between the user server and bit.ly ...

I asked him this early on - 5.2.10.

His CURL extension is active and when I got him to output the CURL config, it matched my own.

Unless he has some kind of CURL installation problem, but then I'd have expected him to have other issues with his WordPress installation.

I assume there doesn't appear to be anything wrong with my code?

David.

BTW, I'm running one PHP version below that - 5.2.9.

I can see some changes were made in 5.2.10. More interestingly, a lot of CURL bugs were fixed in the version after that, although I can't see any that relate to this specific issue...

http://php.net/ChangeLog-5.php

David.

I assume there doesn't appear to be anything wrong with my code?

No, not that I can spot.
Which makes me think that the problem is not in the bug corrections of the last php release.
I have tested it on a 5.2.12-pl0 release, with a CLI binary on Linux.

Do you happen to know which os is running on your user server ?
If it's a window version, maybe there is something in that build...

I'm on a Linux build. Not sure about my user.