CURLOPT_TCP_KEEPIDLE(3)    Library Functions Manual    CURLOPT_TCP_KEEPIDLE(3)

NAME
       CURLOPT_TCP_KEEPIDLE - TCP keep-alive idle time wait

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPIDLE, long delay);

DESCRIPTION
       Pass a long. Sets the delay, in seconds, to wait while the connection
       is idle before sending keepalive probes. Not all operating systems
       support this option.

       The maximum value this accepts is 2147483648. Any larger value is
       capped to this amount.

DEFAULT
       60

PROTOCOLS
       This functionality affects tcp only

EXAMPLE
       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

           /* enable TCP keep-alive for this transfer */
           curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1L);

           /* set keep-alive idle time to 120 seconds */
           curl_easy_setopt(curl, CURLOPT_TCP_KEEPIDLE, 120L);

           /* interval time between keep-alive probes: 60 seconds */
           curl_easy_setopt(curl, CURLOPT_TCP_KEEPINTVL, 60L);

           /* maximum number of keep-alive probes: 3 */
           curl_easy_setopt(curl, CURLOPT_TCP_KEEPCNT, 3L);

           curl_easy_perform(curl);
         }
       }

AVAILABILITY
       Added in curl 7.25.0

RETURN VALUE
       curl_easy_setopt(3) returns a CURLcode indicating success or error.

       CURLE_OK (0) means everything was OK, non-zero means an error occurred,
       see libcurl-errors(3).

SEE ALSO
       CURLOPT_TCP_KEEPALIVE(3), CURLOPT_TCP_KEEPCNT(3),
       CURLOPT_TCP_KEEPINTVL(3)

libcurl                           2025-06-04           CURLOPT_TCP_KEEPIDLE(3)