1---
2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
3SPDX-License-Identifier: curl
4Title: curl_multi_add_handle
5Section: 3
6Source: libcurl
7See-also:
8  - curl_multi_cleanup (3)
9  - curl_multi_get_handles (3)
10  - curl_multi_init (3)
11  - curl_multi_setopt (3)
12  - curl_multi_socket_action (3)
13Protocol:
14  - All
15Added-in: 7.9.6
16---
17
18# NAME
19
20curl_multi_add_handle - add an easy handle to a multi session
21
22# SYNOPSIS
23
24~~~c
25#include <curl/curl.h>
26
27CURLMcode curl_multi_add_handle(CURLM *multi_handle, CURL *easy_handle);
28~~~
29
30# DESCRIPTION
31
32Adds the *easy handle* to the *multi_handle*.
33
34While an easy handle is added to a multi stack, you cannot and you must not
35use curl_easy_perform(3) on that handle. After having removed the easy
36handle from the multi stack again, it is perfectly fine to use it with the
37easy interface again.
38
39If the easy handle is not set to use a shared (CURLOPT_SHARE(3)) cache,
40it is made to use a DNS cache that is shared between all easy handles within
41the multi handle when curl_multi_add_handle(3) is called.
42
43When an easy interface is added to a multi handle, it is set to use a shared
44connection cache owned by the multi handle. Removing and adding new easy
45handles does not affect the pool of connections or the ability to do
46connection reuse.
47
48If you have CURLMOPT_TIMERFUNCTION(3) set in the multi handle (as you
49should if you are working event-based with curl_multi_socket_action(3)
50and friends), that callback is called from within this function to ask for an
51updated timer so that your main event loop gets the activity on this handle to
52get started.
53
54The easy handle remains added to the multi handle until you remove it again
55with curl_multi_remove_handle(3) - even when a transfer with that
56specific easy handle is completed.
57
58You should remove the easy handle from the multi stack before you terminate
59first the easy handle and then the multi handle:
60
611 - curl_multi_remove_handle(3)
62
632 - curl_easy_cleanup(3)
64
653 - curl_multi_cleanup(3)
66
67# %PROTOCOLS%
68
69# EXAMPLE
70
71~~~c
72int main(void)
73{
74  /* init a multi stack */
75  CURLM *multi = curl_multi_init();
76
77  /* create two easy handles */
78  CURL *http_handle = curl_easy_init();
79  CURL *http_handle2 = curl_easy_init();
80
81  /* add individual transfers */
82  curl_multi_add_handle(multi, http_handle);
83  curl_multi_add_handle(multi, http_handle2);
84}
85~~~
86
87# %AVAILABILITY%
88
89# RETURN VALUE
90
91CURLMcode type, general libcurl multi interface error code.
92