---
name: "CURLOPT_FTP_SSL_CCC"
section: "3"
platform: "linux"
package: "curl"
version: "8.23.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLOPT_FTP_SSL_CCC"
---

# CURLOPT\_FTP\_SSL\_CCC(3)

switch off SSL again with FTP after auth

## NAME

CURLOPT\_FTP\_SSL\_CCC - switch off SSL again with FTP after auth

## SYNOPSIS

```
#include <curl/curl.h>
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 remains unencrypted. This allows NAT routers to follow the FTP transaction. Pass a long using one of the values below

- CURLFTPSSL\_CCC\_NONE

  do not 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

This functionality affects ftp only

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    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);
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
```

## HISTORY

**CURLFTPSSL\_**\* enums became *long* types in 8.16.0, prior to this version a *long* cast was necessary when passed to *[curl\_easy\_setopt(3)](/curl_easy_setopt/3.md)*.

## AVAILABILITY

Added in curl 7.16.1

## RETURN VALUE

*[curl\_easy\_setopt(3)](/curl_easy_setopt/3.md)* returns a CURLcode indicating success or error.

CURLE\_OK (0) means everything was OK, non-zero means an error occurred, see *[libcurl-errors(3)](/libcurl-errors/3.md)*.

## SEE ALSO

[**CURLOPT\_FTPSSLAUTH**(3)](/CURLOPT_FTPSSLAUTH/3.md), [**CURLOPT\_PROTOCOLS\_STR**(3)](/CURLOPT_PROTOCOLS_STR/3.md), [**CURLOPT\_USE\_SSL**(3)](/CURLOPT_USE_SSL/3.md)