gnurl_easy_upkeep(3)

✨ gnurl_easy_upkeep(3) — the libgnurl Manual glow-up 💖

okay so this is the gnurl_easy_upkeep(3) page from the libgnurl Manual, and it's literally about keeping connections alive. main character energy for your connections, no cap.

🌸 NAME 🌸

curl_easy_upkeep — Perform any connection upkeep checks. 💅

🎀 SYNOPSIS 🎀

#include <gnurl/curl.h>

CURLcode curl_easy_upkeep(CURL *handle);

🦋 DESCRIPTION 🦋

Some protocols have "connection upkeep" mechanisms. These mechanisms usually send some traffic on existing connections in order to keep them alive; this can prevent connections from being closed due to overzealous firewalls, for example. like, firewalls can be so extra sometimes 😭

Currently the only protocol with a connection upkeep mechanism is HTTP/2: when the connection upkeep interval is exceeded and curl_easy_upkeep(3) is called, an HTTP/2 PING frame is sent on the connection. iconic behavior honestly ✨

This function must be explicitly called in order to perform the upkeep work. The connection upkeep interval is set with CURLOPT_UPKEEP_INTERVAL_MS(3). so yeah, you gotta call it yourself, bestie — it's not doing background magic 🫶

⭐ AVAILABILITY ⭐

Added in 7.62.0. periodt. 💅

💖 RETURN VALUE 💖

On success, returns CURLE_OK.

On failure, returns the appropriate error code.

🌈 EXAMPLE 🌈

CURL *curl = curl_easy_init();
if(curl) {
  /* Make a connection to an HTTP/2 server. */
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

  /* Set the interval to 30000ms / 30s */
  curl_easy_setopt(curl, CURLOPT_UPKEEP_INTERVAL_MS, 30000L);

  curl_easy_perform(curl);

  /* Perform more work here. */

  /* While the connection is being held open, curl_easy_upkeep() can be
     called. If curl_easy_upkeep() is called and the time since the last
     upkeep exceeds the interval, then an HTTP/2 PING is sent. */
  curl_easy_upkeep(curl);

  /* Perform more work here. */

  /* always cleanup */
  curl_easy_cleanup(curl);
}

Cute sign-off: this page is rockin’ libcurl 7.62.0, dated 31 Oct 2018, and it's literally called gnurl_easy_upkeep(3) — bye bestie 💜✨