Verifying File Existence from a URL

Having trouble verifying file existence on a remote server using traditional file system functions? Don't worry, there's an alternative approach that's both quick and efficient.

Using get_headers()

PHP's get_headers() function allows you to retrieve the HTTP response headers for a given URL. When checking file existence, you're interested in whether the server responds with a 200 OK status code, indicating the presence of the file.

Code Example

Here's an example function to check file existence:

function file_exists_url($url){
   $headers=get_headers($url);
   return stripos($headers[0],"200 OK")?true:false;
}

Usage

You can use the function like this:

if(file_exists_url("http://www.example.com/file.txt"))
   echo "File exists";
else
   echo "File does not exist";

Advantages

This method is more efficient than using CURL, which can be an overkill for simply checking file existence. It also doesn't require any PHP extensions or external libraries.