CURLOPT_MAXAGE_CONN(3) Library Functions Manual CURLOPT_MAXAGE_CONN(3)

CURLOPT_MAXAGE_CONN - max idle time allowed for reusing a connection

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

Pass a long as parameter containing age - the maximum time in seconds allowed for an existing connection to have been idle to be considered for reuse for this request.

The "connection cache" holds previously used connections. When a new request is to be done, libcurl considers any connection that matches for reuse. The CURLOPT_MAXAGE_CONN(3) limit prevents libcurl from trying too old connections for reuse, since old connections have a higher risk of not working and thus trying them is a performance loss and sometimes service loss due to the difficulties to figure out the situation. If a connection is found in the cache that is older than this set age, it is closed instead.

118 seconds

This functionality affects all supported protocols

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    /* only allow 30 seconds idle time */
    curl_easy_setopt(curl, CURLOPT_MAXAGE_CONN, 30L);
    curl_easy_perform(curl);
  }
}

Added in curl 7.65.0

Returns CURLE_OK.

CURLOPT_FORBID_REUSE(3), CURLOPT_FRESH_CONNECT(3), CURLOPT_MAXLIFETIME_CONN(3), CURLOPT_TIMEOUT(3)

2024-09-18 libcurl