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CURLOPT_TCP_KEEPCNT

Section: C Library Functions (3)
Updated: 202-0-19
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NAME

CURLOPT_TCP_KEEPCNT - Maximum number of TCP keep-alive probes

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPCNT, long cnt);

DESCRIPTION

Pass a long. Sets the number of probes to send before dropping the connection. Not all operating systems support this option. (Added in 8.9.0)

The maximum value this option accepts is INT_MAX or whatever your system allows. Any larger value is capped to this amount.

DEFAULT

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

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

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

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

    curl_easy_perform(curl);
  }
}

AVAILABILITY

Added in curl 8.9.0

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).