The following command enables cURL’s “auto encoding” mode, where it will announce to the server which encoding methods it supports (via the Accept-Encoding header), and then automatically decompress the response for you:
// Allow cURL to use gzip compression, or any other supported encoding
// A blank string activates 'auto' mode
curl_setopt($ch, CURLOPT_ENCODING , '');
If you specifically want to force the header to be Accept-Encoding: gzip you can use this command instead:
// Allow cURL to use gzip compression, or any other supported encoding
curl_setopt($ch, CURLOPT_ENCODING , 'gzip');
Read more in the PHP documentation: curl_setopt.
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