.\" generated by cd2nroff 0.1 from CURLOPT_TCP_KEEPINTVL.md
.TH CURLOPT_TCP_KEEPINTVL 3 "2024-11-18" libcurl
.SH NAME
CURLOPT_TCP_KEEPINTVL \- TCP keep\-alive interval
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPINTVL, long interval);
.fi
.SH DESCRIPTION
Pass a long. Sets the interval, in seconds, to wait between sending keepalive
probes. Not all operating systems support this option. (Added in 7.25.0)

The maximum value this accepts is 2147483648. Any larger value is capped to
this amount.
.SH DEFAULT
60
.SH PROTOCOLS
This functionality affects tcp only
.SH EXAMPLE
.nf
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);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.25.0
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH SEE ALSO
.BR CURLOPT_TCP_KEEPALIVE (3),
.BR CURLOPT_TCP_KEEPCNT (3),
.BR CURLOPT_TCP_KEEPIDLE (3)