curl/docs/libcurl/opts/CURLOPT_FTP_SSL_CCC.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

1.6 KiB

c SPDX-License-Identifier Title Section Source Protocol See-also
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. curl CURLOPT_FTP_SSL_CCC 3 libcurl
FTP
CURLOPT_FTPSSLAUTH (3)
CURLOPT_PROTOCOLS_STR (3)
CURLOPT_USE_SSL (3)

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

EXAMPLE

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);
  }
}

AVAILABILITY

Added in 7.16.1

RETURN VALUE

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