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.TH CURLOPT_FTP_SSL_CCC 3 "19 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_FTP_SSL_CCC \- switch off SSL again with FTP after auth
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_SSL_CCC,
                          long how);
.fi
.SH 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 remains unencrypted. This allows NAT routers to follow
the FTP transaction. Pass a long using one of the values below
.IP CURLFTPSSL_CCC_NONE
do not attempt to use CCC.
.IP CURLFTPSSL_CCC_PASSIVE
Do not initiate the shutdown, but wait for the server to do it. Do not send a
reply.
.IP CURLFTPSSL_CCC_ACTIVE
Initiate the shutdown and wait for a reply.
.SH DEFAULT
CURLFTPSSL_CCC_NONE
.SH PROTOCOLS
FTP
.SH EXAMPLE
.nf
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    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, (long)CURLFTPSSL_CCC_ACTIVE);
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in 7.16.1
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_FTPSSLAUTH (3),
.BR CURLOPT_PROTOCOLS_STR (3),
.BR CURLOPT_USE_SSL (3)