GNURLOPT_ALTSVC(3)

🎀 CURLOPT_ALTSVC: set alt-svc cache file name 🎀

okay so bestie, welcome to the GNURLOPT_ALTSVC(3) page from the curl_easy_setopt options crew. We're talking alt-svc cache files, and yes, it's giving very specific libcurl behavior 💅

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✨ NAME ✨

CURLOPT_ALTSVC — set alt-svc cache file name

🌸 SYNOPSIS 🌸

#include <gnurl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ALTSVC, char *filename);

🧪 EXPERIMENTAL 🧪

Warning, bestie: this feature is early code and is marked as experimental. It can only be enabled by explicitly telling configure with --enable-alt-svc. You are advised to not ship this in production before the experimental label is removed. No cap, that's the actual warning 🫶

💖 DESCRIPTION 💖

You pass in a pointer to a filename, and that tells libcurl to use that file as the Alt-Svc cache. It reads existing cache contents from it, and it may also write it back after a transfer — unless CURLALTSVC_READONLYFILE is set in CURLOPT_ALTSVC_CTRL(3).

Specify a blank file name ("") to make libcurl not load from a file at all. Literally blank, bestie 🫧

🦋 DEFAULT 🦋

NULL. The alt-svc cache is not read nor written to file.

🌈 PROTOCOLS 🌈

HTTPS

🍓 EXAMPLE 🍓

CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_ALTSVC_CTRL, CURLALTSVC_H1);
  curl_easy_setopt(curl, CURLOPT_ALTSVC, "altsvc-cache.txt");
  curl_easy_perform(curl);
}

⭐ AVAILABILITY ⭐

Added in 7.64.1

💜 RETURN VALUE 💜

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. Simple as that ✨

👑 SEE ALSO 👑

• CURLOPT_ALTSVC_CTRL(3)
• CURLOPT_CONNECT_TO(3)
• CURLOPT_RESOLVE(3)
• CURLOPT_COOKIEFILE(3),

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k bye bestie — this page is from libcurl 7.64.1, dated 5 Feb 2019, and it's literally the GNURLOPT_ALTSVC(3) manual page 💅✨