CURLOPT\_FTP\_SSL\_CCC(3) Library Functions Manual CURLOPT\_FTP\_SSL\_CCC(3)

# [NAME](#NAME)

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

# [SYNOPSIS](#SYNOPSIS)

```
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_SSL_CCC,


                          long how);
```

# [DESCRIPTION](#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](#CURLFTPSSL_CCC_NONE)

do not attempt to use CCC.

[CURLFTPSSL\_CCC\_PASSIVE](#CURLFTPSSL_CCC_PASSIVE)

Do not initiate the shutdown, but wait for the server to do it. Do not send a reply.

[CURLFTPSSL\_CCC\_ACTIVE](#CURLFTPSSL_CCC_ACTIVE)

Initiate the shutdown and wait for a reply.

# [DEFAULT](#DEFAULT)

CURLFTPSSL\_CCC\_NONE

# [PROTOCOLS](#PROTOCOLS)

This functionality affects ftp only

# [EXAMPLE](#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](#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)*](/man/os/curl/curl_easy_setopt.3).

# [AVAILABILITY](#AVAILABILITY)

Added in curl 7.16.1

# [RETURN VALUE](#RETURN_VALUE)

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

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

# [SEE ALSO](#SEE_ALSO)

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

2026-10-22 libcurl

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Document: CURLOPT_FTP_SSL_CCC(3) from curl 8.23.0-r2 (Chainguard OS)
Source: https://github.com/curl/curl.git