CURLOPT_PROXY_PINNEDPUBLICKEY

CURLOPT_PROXY_PINNEDPUBLICKEY is one of the accepted parameters for curl_setopt parameter #2.

CURLOPT_PROXY_PINNEDPUBLICKEY — Set the pinned public key for HTTPS proxy. The string can be the file name of the pinned public key which is expected to be in a PEM or DER file format. The string can also be any number of base64 encoded sha256 hashes preceded by sha256// and separated by ;. Available as of PHP 7.3.0 and cURL 7.52.0.

CURLOPT_PROXY_PINNEDPUBLICKEY = 10263;