请问 FTP over SSL with libcurl

<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_URL, "ftp:127.0.0.1:990/");<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_USERNAME, "username");<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_PASSWORD, "password");<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_DIRLISTONLY, 1L);<br />
 <br />
/*<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_FTP_SSL_CCC, CURLFTPSSL_CCC_NONE);<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_SSL_VERIFYPEER, 1L);<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_SSL_VERIFYHOST, 2L);<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_FTPSSLAUTH, CURLFTPAUTH_TLS);<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1);<br />
*/<br />
 <br />
/*<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_TLSAUTH_TYPE, 1L);<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_TLSAUTH_USERNAME, "tms");<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_TLSAUTH_PASSWORD, "ewstms");<br />
*/<br />
 <br />
/*<br />
code = curl_easy_setopt(ftp_handle, CURLOPT_USE_SSL, CURLUSESSL_ALL);<br />
*/<br />
 <br />
code = curl_easy_setopt(ftp_handle, CURLOPT_VERBOSE, 1L);<br />
<br />
CURLcode res = curl_easy_perform(ftp_handle);<br />