NAME

       CURLOPT_TCP_KEEPALIVE - TCP keep-alive probing

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPALIVE, long probe);

DESCRIPTION

       Pass  a  long.  If set to 1, TCP keepalive probes will be sent. The delay and frequency of
       these probes can be controlled by the CURLOPT_TCP_KEEPIDLE(3) and CURLOPT_TCP_KEEPINTVL(3)
       options,  provided  the  operating  system  supports  them. Set to 0 (default behavior) to
       disable keepalive probes

DEFAULT

       0

PROTOCOLS

       All

EXAMPLE

       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);

         /* 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);
       }

AVAILABILITY

       Added in 7.25.0

RETURN VALUE

       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_TCP_KEEPIDLE(3), CURLOPT_TCP_KEEPINTVL(3),