GNURLOPT_U...BUFFERSIZE(3)

💅 GNURLOPT_UPLOAD_BUFFERSIZE(3) — like, the upload-buffer-size one, bestie

okay so real talk, this one lives in the gnurl/curl.h corner of the world (that's the gnurl flavour of the curl_easy_setopt options crew, iykyk), and it's genuinely one of those "small flag, big mood" situations 🫶

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✨ NAME ✨

CURLOPT_UPLOAD_BUFFERSIZE — set your preferred upload buffer size, queen 👑

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🌸 SYNOPSIS 🌸

#include <gnurl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD_BUFFERSIZE, long size);

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🦋 DESCRIPTION 🦋

so you pass a long that says what size (in bytes, btw) you want the upload buffer in libcurl to be. and then libcurl goes and uses a bigger buffer that gets passed to the next layer down the stack so it can get sent off. and honestly? in some setups, and for some protocols, having a larger upload buffer is a huge performance benefit. like, not me being dramatic, it's literally in the docs. 🔥

⚠️ but listen — this is treated as a request, not an order. you are not guaranteed to actually get the size you asked for. the vibes are advisory only. 😭

the upload buffer size is by default 64 kilobytes. the maximum buffer size you're allowed to set is 2 megabytes. the minimum buffer size you're allowed to set is 16 kilobytes. so like, stay in your lane between those, bestie 💅

and since curl 7.61.1 the upload buffer is allocated on-demand — so if the handle isn't used for upload, the buffer will not be allocated at all. we love a lazy-allocating icon who doesn't do work that isn't needed ✨

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🎀 DEFAULT 🎀

64 kB — the standard-issue vibe, no cap

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🌈 PROTOCOLS 🌈

All of them. every single one. main character energy across the board 👑

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💖 EXAMPLE 💖

CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/foo.bin");

  /* ask libcurl to allocate a larger upload buffer */
  curl_easy_setopt(curl, CURLOPT_UPLOAD_BUFFERSIZE, 120000L);

  ret = curl_easy_perform(curl);

  curl_easy_cleanup(curl);
}

see that 120000L? that's the "please give me a bigger buffer" ask 🥺 and the comment in the middle is literally there to explain itself, we stan a self-documenting codebase.

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⭐ AVAILABILITY ⭐

Added in 7.62.0. so if you're on something older, this option is giving "not invited to the party" 💀

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🧚 RETURN VALUE 🧚

returns CURLE_OK if the option is supported — slay ✅

and returns CURLE_UNKNOWN_OPTION if it's not — sad but valid 🙈

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🔥 SEE ALSO 🔥

• CURLOPT_BUFFERSIZE(3)
• CURLOPT_READFUNCTION(3)

(that trailing comma in the original? iconic. we keep it. periodt.)

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and that's the whole page, bestie 💜 it's from libcurl 7.62.0, dated 18 Aug 2018, filed under the very dramatic GNURLOPT_U...BUFFERSIZE(3) header because apparently even manpage titles get the abridged treatment 🎀 go forth and buffer responsibly 🦋