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Hi, I've a question about libcurl and proxy

From: Kuan-Sheng Chen via curl-library <>
Date: Mon, 24 Sep 2018 12:11:16 -0700

I'm Kuan-Sheng from FaceBook. Just Recently I'm working on a project about
differentiating proxy's error from server's error using libcurl. The way
I'm doing this is by making sure that libcurl has finished it's http
tunneling with the proxy, so if there's an error after that, I would make
it a server error, and vice versa.

  The problem now I'm facing is that the only way to get the http tunneling
messages is throw enabling CURLOPT_VERBOSE, and to check these Verbose
message in a coding way I dumped it to a file with CURLOPT_STDERR, and
checked it line by line so as to "observer" the operation of http
tunneling. But this is not gonna be a scalable way since file operation has
high overhead for system. My question is that can we get these Verbose
information as soon as any single operation is done instead of having to
wait for the whole curl ends and printing the entire debug message ?
Something I'm expecting is like a callback function that stores curl's
operation(ex: http tunneling in my case) and maybe pass it to a string so
that I can check it during curl's execution. Thank you Kuan-Sheng

Received on 2018-09-24