curl/docs/libcurl/opts/CURLOPT_TELNETOPTIONS.md
Daniel Stenberg e694c8284a
docs/libcurl/opts: clarify the return values
Expand a little.

- mention the type name of the return code
- avoid stating which exact return codes that might be returned, as that
  varies over time, builds and conditions
- avoid stating some always return OK
- refer to the manpage documenting all the return codes

Closes #15900
2025-01-02 17:13:33 +01:00

1.6 KiB

c SPDX-License-Identifier Title Section Source See-also Protocol Added-in
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. curl CURLOPT_TELNETOPTIONS 3 libcurl
CURLOPT_HTTPHEADER (3)
CURLOPT_QUOTE (3)
TELNET
7.7

NAME

CURLOPT_TELNETOPTIONS - set of telnet options

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TELNETOPTIONS,
                          struct curl_slist *cmds);

DESCRIPTION

Provide a pointer to a curl_slist with variables to pass to the telnet negotiations. The variables should be in the format <option=value>. libcurl supports the options TTYPE, XDISPLOC and NEW_ENV. See the TELNET standard for details.

Using this option multiple times makes the last set list override the previous ones. Set it to NULL to disable its use again.

libcurl does not copy the list, it needs to be kept around until after the transfer has completed.

DEFAULT

NULL

%PROTOCOLS%

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    struct curl_slist *options;
    options = curl_slist_append(NULL, "TTTYPE=vt100");
    options = curl_slist_append(options, "USER=foobar");
    curl_easy_setopt(curl, CURLOPT_URL, "telnet://example.com/");
    curl_easy_setopt(curl, CURLOPT_TELNETOPTIONS, options);
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
    curl_slist_free_all(options);
  }
}

%AVAILABILITY%

RETURN VALUE

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).