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.TH CURLOPT_TCP_KEEPINTVL 3 "19 Jun 2014" libcurl 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, that the operating system will
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 will be capped
to this amount.
.SH DEFAULT
60
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
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);

  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Always
.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), " CURLOPT_TCP_KEEPIDLE "(3), "