DragonFly On-Line Manual Pages
CURLOPT_FTPPORT(3) curl_easy_setopt options CURLOPT_FTPPORT(3)
CURLOPT_FTPPORT - make FTP transfer active
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTPPORT, char *spec);
Pass a pointer to a null-terminated string as parameter. It specifies
that the FTP transfer will be made actively and the given string will
be used to get the IP address to use for the FTP PORT instruction.
The PORT instruction tells the remote server to connect to our
specified IP address. The string may be a plain IP address, a host
name, a network interface name (under Unix) or just a '-' symbol to let
the library use your system's default IP address. Default FTP
operations are passive, and thus won't use PORT.
The address can be followed by a ':' to specify a port, optionally
followed by a '-' to specify a port range. If the port specified is 0,
the operating system will pick a free port. If a range is provided and
all ports in the range are not available, libcurl will report
CURLE_FTP_PORT_FAILED for the handle. Invalid port/range settings are
ignored. IPv6 addresses followed by a port or portrange have to be in
brackets. IPv6 addresses without port/range specifier can be in
Examples with specified ports:
You disable PORT again and go back to using the passive version by
setting this option to NULL.
The application does not have to keep the string around after setting
CURL *curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com/old-server/file.txt");
curl_easy_setopt(curl, CURLOPT_FTPPORT, "-");
ret = curl_easy_perform(curl);
Port range support was added in 7.19.5
Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if
not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.
libcurl 7.76.0 November 4, 2020 CURLOPT_FTPPORT(3)