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Re: Application to request http2 content with multiplexed multiple streams

From: Daniel Stenberg via curl-library <>
Date: Tue, 7 Aug 2018 22:56:01 +0200 (CEST)

On Tue, 7 Aug 2018, Rajvardhan Deshmukh via curl-library wrote:

> 1. I have written a code [1] to download 2 files at a time (multiplexed
> using 2 streams). And i intend to download 100 total files. Can you verify
> if i'm reusing the connection properly (concern as i use curl_easy_init();
> for each url). But this doc [2] says as long as i use the same multi handle
> i should be good.

I looks fine, and you can verify yourself by reading the verbose output as it
states clearly when it reuses connections.

But I can also tell you that your program will busy-loop and use 100% CPU
for as long as there are transfers going and that is wasteful and ineffective.
Don't do curl_multi_perform() in a loop like that.

> 2. I also need to identify the api which requests chunks of data (so that
> not all response data is written to the memory at the same time, but as
> multiple of chunks).

CURLOPT_WRITEFUNCTION is the *only* API you can receive data with if you don't
want to store it directly to a file. libcurl can't deliver data in any other
way than piece by piece.

Received on 2018-08-07