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Daniel Gustafsson 8d67c61c47 curldown: Fix email address in Copyright

The curldown conversion accidentally replaced daniel@haxx.se with
just daniel.se.  This reverts back to the proper email address in
the curldown docs as well as in a few other stray places where it
was incorrect (while unrelated to curldown).

Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Closes: #12997

2024-02-28 11:28:10 +01:00

1.9 KiB

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SPDX-License-Identifier

Title

Section

Source

See-also

curl

CURLOPT_RESOLVER_START_FUNCTION

libcurl

CURLOPT_PREREQFUNCTION (3)

CURLOPT_RESOLVER_START_DATA (3)

NAME

CURLOPT_RESOLVER_START_FUNCTION - callback called before a new name resolve is started

SYNOPSIS

#include <curl/curl.h>

int resolver_start_cb(void *resolver_state, void *reserved, void *userdata);

CURLcode curl_easy_setopt(CURL *handle,
                          CURLOPT_RESOLVER_START_FUNCTION,
                          resolver_start_cb);

DESCRIPTION

Pass a pointer to your callback function, which should match the prototype shown above.

This callback function gets called by libcurl every time before a new resolve request is started.

resolver_state points to a backend-specific resolver state. Currently only the ares resolver backend has a resolver state. It can be used to set up any desired option on the ares channel before it is used, for example setting up socket callback options.

reserved is reserved.

userdata is the user pointer set with the CURLOPT_RESOLVER_START_DATA(3) option.

The callback must return 0 on success. Returning a non-zero value causes the resolve to fail.

DEFAULT

NULL (No callback)

PROTOCOLS

All

EXAMPLE

static int start_cb(void *resolver_state, void *reserved,
                    void *userdata)
{
  (void)reserved;
  printf("Received resolver_state=%p userdata=%p\n",
         resolver_state, userdata);
  return 0;
}

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_RESOLVER_START_FUNCTION, start_cb);
    curl_easy_setopt(curl, CURLOPT_RESOLVER_START_DATA, curl);
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

AVAILABILITY

Added in 7.59.0

RETURN VALUE

Returns CURLE_OK

1.9 KiB Raw Blame History