CURLOPT_TCP_KEEPALIVE(3)

CURLOPT_TCP_KEEPALIVE3

Tcp keep-alive probing

Usage

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_KEEPALIVE, long probe);

Overview

Pass a long. If set to 1, TCP keepalive probes are used. 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

Examples

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);
    /* 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);
  }
}

Return value

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

Releases

79 releases since OS X 10.10; the text changed 14 times.

  1. 10.10–10.10.4
  2. 10.10.5–10.11.6
  3. 10.12–10.12.5
  4. 10.12.6–10.14.6
  5. 10.15–11.5
  6. 12.0.1–12.2
  7. 12.3–12.5
  8. 13.0
  9. 13.1
  10. 13.2
  11. 13.3
  12. 13.4
  13. 13.5–14.1
  14. 14.2–14.4
  15. 14.5–26.5

Availability

Added in 7.25.0

From curl 166.0.0.0.1 in macOS 26.5. Parsed by carta from the page's man source.