GNURLINFO_OS_ERRNO(3)

📦 version 7.72.0, in nixos 26.05, nixpkgs unstable

💅 GNURLINFO_OS_ERRNO(3) — like, the curl_easy_getinfo options era 🎀

okay bestie, so this one lives in the curl_easy_getinfo options family (that's the manual name, iykyk) and it's literally about catching the errno from a failed connect. let's get into it ✨

🌸 NAME 🌸

CURLINFO_OS_ERRNO — grab the errno number from the last connect failure 🫶

✨ SYNOPSIS ✨

#include <gnurl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_OS_ERRNO, long *errnop);

like, that's the whole vibe. you hand it a long pointer and it fills it in 🎀

💖 DESCRIPTION 💖

so here's the tea: you pass a pointer to a long, and it receives the errno variable from a connect failure. that's it, that's the whole thing 💅

⚠️ important caveat, no cap: the value is only set on failure. it is not reset when an operation succeeds. so if you're out here reading it after a win, you're reading stale vibes, bestie 😭

also highkey relevant: the number is OS and system specific. so like, don't go comparing it across machines expecting matching energy 🌈

🦋 PROTOCOLS 🦋

All 👑

🍓 EXAMPLE 🍓

CURL *curl = curl_easy_init();
if(curl) {
  CURLcode res;
  curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");
  res = curl_easy_perform(curl);
  if(res != CURLE_OK) {
    long error;
    res = curl_easy_getinfo(curl, CURLINFO_OS_ERRNO, &error);
    if(res && error) {
      printf("Errno: %ld\n", error);
    }
  }
  curl_easy_cleanup(curl);
}

look at that little if(res && error) check doing its main character thing 🔥

⭐ AVAILABILITY ⭐

added in 7.12.2 — vintage but iconic, fr fr 🎀

💜 RETURN VALUE 💜

  • returns CURLE_OK if the option is supported ✅
  • returns CURLE_UNKNOWN_OPTION if it's not 🙈

that's the whole vibe check.

🌟 SEE ALSO 🌟

okay that's the page!! mwah 💋 this was libcurl 7.44.0, dated 1 Sep 2015, and yes she's giving GNURLINFO_OS_ERRNO(3) energy the whole way through — go forth and debug your connects, bestie 🧚‍♀️💖

📦 where this page comes from