**************************************************************************
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* Project ___| | | | _ \| |
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*
* Copyright (C) 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
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* furnished to do so, under the terms of the COPYING file.
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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**************************************************************************

CURLOPT_DOH_URL - provide the DNS-over-HTTPS URL #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_URL, char *URL); Pass in a pointer to a URL for the DOH server to use for name resolving. The parameter should be a char * to a null-terminated string which must be URL-encoded in the following format: "https://host:port/path". It MUST specify a HTTPS URL. libcurl doesn't validate the syntax or use this variable until the transfer is issued. Even if you set a crazy value here, curl_easy_setopt(3) will still return CURLE_OK. curl sends POST requests to the given DNS-over-HTTPS URL. To find the DOH server itself, which might be specified using a name, libcurl will use the default name lookup function. You can bootstrap that by providing the address for the DOH server with CURLOPT_RESOLVE(3). Disable DOH use again by setting this option to NULL. NULL - there is no default DOH URL. If this option isn't set, libcurl will use the default name resolver. All

CURL *curl = curl_easy_init();
if(curl) {
 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
 curl_easy_setopt(curl, CURLOPT_DOH_URL, "https://dns.example.com");
 curl_easy_perform(curl);
}

Added in 7.62.0 Returns CURLE_OK on success or CURLE_OUT_OF_MEMORY if there was insufficient heap space. Note that curl_easy_setopt(3) won't actually parse the given string so given a bad DOH URL, curl will not detect a problem until it tries to resolve a name with it. CURLOPT_VERBOSE "(3), " CURLOPT_RESOLVE "(3), "