CURLOPT_HEADEROPT(3) Library Functions Manual CURLOPT_HEADEROPT(3) NAME CURLOPT_HEADEROPT - send HTTP headers to both proxy and host or separately SYNOPSIS #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADEROPT, long bitmask); DESCRIPTION Pass a long that is a bitmask of options of how to deal with headers. The two mutually exclusive options are: CURLHEADER_UNIFIED - the headers specified in CURLOPT_HTTPHEADER(3) are used in requests both to servers and proxies. With this option enabled, CURLOPT_PROXYHEADER(3) does not have any effect. CURLHEADER_SEPARATE - makes CURLOPT_HTTPHEADER(3) headers only get sent to a server and not to a proxy. Proxy headers must be set with CURLOPT_PROXYHEADER(3) to get used. Note that if a non-CONNECT request is sent to a proxy, libcurl sends both server headers and proxy headers. When doing CONNECT, libcurl sends CURLOPT_PROXYHEADER(3) headers only to the proxy and then CURLOPT_HTTPHEADER(3) headers only to the server. DEFAULT CURLHEADER_SEPARATE (changed in 7.42.1, used CURLHEADER_UNIFIED before then) PROTOCOLS This functionality affects http only EXAMPLE int main(void) { CURL *curl = curl_easy_init(); if(curl) { CURLcode ret; struct curl_slist *list; list = curl_slist_append(NULL, "Shoesize: 10"); list = curl_slist_append(list, "Accept:"); curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/"); curl_easy_setopt(curl, CURLOPT_PROXY, "http://localhost:8080"); curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list); /* HTTPS over a proxy makes a separate CONNECT to the proxy, so tell libcurl to not send the custom headers to the proxy. Keep them separate. */ curl_easy_setopt(curl, CURLOPT_HEADEROPT, CURLHEADER_SEPARATE); ret = curl_easy_perform(curl); curl_slist_free_all(list); curl_easy_cleanup(curl); } } AVAILABILITY Added in curl 7.37.0 RETURN VALUE Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. SEE ALSO CURLOPT_HTTPHEADER(3), CURLOPT_PROXYHEADER(3) libcurl 2024-11-07 CURLOPT_HEADEROPT(3)