1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: CURLOPT_TCP_KEEPINTVL 5Section: 3 6Source: libcurl 7See-also: 8 - CURLOPT_TCP_KEEPALIVE (3) 9 - CURLOPT_TCP_KEEPIDLE (3) 10 - CURLOPT_TCP_KEEPCNT (3) 11Protocol: 12 - TCP 13--- 14 15# NAME 16 17CURLOPT_TCP_KEEPINTVL - TCP keep-alive interval 18 19# SYNOPSIS 20 21~~~c 22#include <curl/curl.h> 23 24CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPINTVL, long interval); 25~~~ 26 27# DESCRIPTION 28 29Pass a long. Sets the interval, in seconds, to wait between sending keepalive 30probes. Not all operating systems support this option. (Added in 7.25.0) 31 32The maximum value this accepts is 2147483648. Any larger value is capped to 33this amount. 34 35# DEFAULT 36 3760 38 39# EXAMPLE 40 41~~~c 42int main(void) 43{ 44 CURL *curl = curl_easy_init(); 45 if(curl) { 46 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); 47 48 /* enable TCP keep-alive for this transfer */ 49 curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1L); 50 51 /* set keep-alive idle time to 120 seconds */ 52 curl_easy_setopt(curl, CURLOPT_TCP_KEEPIDLE, 120L); 53 54 /* interval time between keep-alive probes: 60 seconds */ 55 curl_easy_setopt(curl, CURLOPT_TCP_KEEPINTVL, 60L); 56 57 /* maximum number of keep-alive probes: 3 */ 58 curl_easy_setopt(curl, CURLOPT_TCP_KEEPCNT, 3L); 59 60 curl_easy_perform(curl); 61 } 62} 63~~~ 64 65# AVAILABILITY 66 67Always 68 69# RETURN VALUE 70 71Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. 72