1---
2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
3SPDX-License-Identifier: curl
4Title: CURLOPT_TCP_KEEPCNT
5Section: 3
6Source: libcurl
7See-also:
8  - CURLOPT_TCP_KEEPALIVE (3)
9  - CURLOPT_TCP_KEEPIDLE (3)
10  - CURLOPT_TCP_KEEPINTVL (3)
11Protocol:
12  - TCP
13Added-in: 8.9.0
14---
15
16# NAME
17
18CURLOPT_TCP_KEEPCNT - Maximum number of TCP keep-alive probes
19
20# SYNOPSIS
21
22~~~c
23#include <curl/curl.h>
24
25CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPCNT, long cnt);
26~~~
27
28# DESCRIPTION
29
30Pass a long. Sets the number of probes to send before dropping
31the connection. Not all operating systems support this option.
32(Added in 8.9.0)
33
34The maximum value this option accepts is INT_MAX or whatever your
35system allows.
36Any larger value is capped to this amount.
37
38# DEFAULT
39
409
41
42# %PROTOCOLS%
43
44# EXAMPLE
45
46~~~c
47int main(void)
48{
49  CURL *curl = curl_easy_init();
50  if(curl) {
51    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
52
53    /* enable TCP keep-alive for this transfer */
54    curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1L);
55
56    /* set keep-alive idle time to 120 seconds */
57    curl_easy_setopt(curl, CURLOPT_TCP_KEEPIDLE, 120L);
58
59    /* interval time between keep-alive probes: 60 seconds */
60    curl_easy_setopt(curl, CURLOPT_TCP_KEEPINTVL, 60L);
61
62    /* maximum number of keep-alive probes: 3 */
63    curl_easy_setopt(curl, CURLOPT_TCP_KEEPCNT, 3L);
64
65    curl_easy_perform(curl);
66  }
67}
68~~~
69
70# %AVAILABILITY%
71
72# RETURN VALUE
73
74Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
75