如何使用PHP中的CURLOPT_FILE判断curl下载是否完成

Question

I have a function that downloads a specific zip file from a remote server to my local Windows server. The file ranges in size from 1-10 mb and I want my script to wait until it's complete. How can I tell with certainty that it's done? The actual downloading works fine.

The function is:

function get_download($url, $path) 
{ 
    $curl = curl_init(); 
    curl_setopt($curl, CURLOPT_URL,$url); 
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 0); 
    curl_setopt($curl, CURLOPT_RETURNTRANSFER,1); 
    curl_setopt($curl, CURLOPT_COOKIEFILE, 'cookie2.txt'); 
    curl_setopt($curl, CURLOPT_FILE, $path);
    $results = curl_exec($curl); 
    return $results; 
}

I thought I would get the size of the remote file first then compare to the local file size. However, this doesn't seem to work. Not sure if its a function of the file being a .zip file but it always returns -1 or -11. I tried this function:

function remotefileSize($url) 
{
    $curl = curl_init($url);
    curl_setopt($curl, CURLOPT_NOBODY, 1);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 0);
    curl_setopt($curl, CURLOPT_HEADER, 0);
    curl_setopt($curl, CURLOPT_FOLLOWLOCATION, 1);
    curl_setopt($curl, CURLOPT_MAXREDIRS, 3);
    curl_exec($curl);
    $filesize = curl_getinfo($curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD);
    curl_close($curl);
    return $filesize;
}

Answer 1

Did you see anything on your browser that shows Unknown time remaining or Unknown bytes remaining while downloading a file? It is because the browser couldn't retrieve the size and failed to calculate remaining time or size. This is what is happening with you. Your filesize retrieval code is correct.

Another reason could be: Sometime the server doesn't support the HEAD request(when you use CURLOPT_NOBODY ).