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.TH CURLOPT_TCP_KEEPINTVL 3 "January 02, 2017" "libcurl 7.66.0" "curl_easy_setopt options"

.SH NAME
CURLOPT_TCP_KEEPINTVL \- set TCP keep-alive interval
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPINTVL, long interval);
.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)
.SH DEFAULT
60
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "http://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), "