CURLOPT_PROXYHEADER(3) Library Functions Manual CURLOPT_PROXYHEADER(3)

CURLOPT_PROXYHEADER - set of HTTP headers to pass to proxy

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXYHEADER,
                          struct curl_slist *headers);

Pass a pointer to a linked list of HTTP headers to pass in your HTTP request sent to a proxy. The rules for this list is identical to the CURLOPT_HTTPHEADER(3) option's.

The headers set with this option is only ever used in requests sent to a proxy - when there is also a request sent to a host.

The first line in a request (containing the method, usually a GET or POST) is NOT a header and cannot be replaced using this option. Only the lines following the request-line are headers. Adding this method line in this list of headers causes your request to send an invalid header.

Pass a NULL to this to reset back to no custom headers.

NULL

HTTP

int main(void)
{
  CURL *curl = curl_easy_init();
  struct curl_slist *list;
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    curl_easy_setopt(curl, CURLOPT_PROXY, "http://proxy.example.com:80");
    list = curl_slist_append(NULL, "Shoesize: 10");
    list = curl_slist_append(list, "Accept:");
    curl_easy_setopt(curl, CURLOPT_PROXYHEADER, list);
    curl_easy_perform(curl);
    curl_slist_free_all(list); /* free the list again */
  }
}

Added in 7.37.0

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

CURLOPT_HEADEROPT(3), CURLOPT_HTTPHEADER(3)

March 12 2024 libcurl