Pointer to pass to the ssh key callback
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSH_KEYDATA, void *pointer);
Pass a void * as parameter. This pointer will be passed along verbatim to the callback set with CURLOPT_SSH_KEYFUNCTION(3).
SFTP and SCP
Added in 7.19.6
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.