CURLOPT_FTP_SSL_CCC

Section: curl_easy_setopt options (3)
Updated: November 04, 2020
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NAME

CURLOPT_FTP_SSL_CCC - switch off SSL again with FTP after auth

SYNOPSIS

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_SSL_CCC,
long how);

DESCRIPTION

If enabled, this option makes libcurl use CCC (Clear Command Channel). It shuts down the SSL/TLS layer after authenticating. The rest of the control channel communication will be unencrypted. This allows NAT routers to follow the FTP transaction. Pass a long using one of the values below

CURLFTPSSL_CCC_NONE: Don't attempt to use CCC.
CURLFTPSSL_CCC_PASSIVE: Do not initiate the shutdown, but wait for the server to do it. Do not send a reply.
CURLFTPSSL_CCC_ACTIVE: Initiate the shutdown and wait for a reply.

DEFAULT

CURLFTPSSL_CCC_NONE

PROTOCOLS

FTP

EXAMPLE

CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com/file.txt");
  curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_CONTROL);
  /* go back to clear-text FTP after authenticating */
  curl_easy_setopt(curl, CURLOPT_FTP_SSL_CCC, CURLFTPSSL_CCC_ACTIVE);
  ret = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}

AVAILABILITY

Added in 7.16.1

RETURN VALUE

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.