Curl don't have separate thread except for name resolving only if enabled.
Write callback will be called from the thread where perform called. Hope
curl document have clear info regarding ur question

> Message: 1
> Date: Thu, 6 Sep 2012 21:24:46 +0000
> From: "Mayank Kumar (mayankum)" <mayankum_at_cisco.com>
> To: "curl-library_at_cool.haxx.se" <curl-library_at_cool.haxx.se>
> Subject: Help with Curl Library to extract socket and establish
> communication
> Message-ID:
> <EDC505415B5EF74C80596BD24619C1030F5A730C_at_xmb-rcd-x07.cisco.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Here is the scenario I want to execute :-
>
>
> 1. Use curl to post some data to a server using curl_easy_perform
>
> 2. Extract the socket used in 1 using CURLINFO_LASTSOCKET
>
> 3. Use the socket got from 2 to determine and receive further data
from the server(using select and recv on the socket) from time to time on
an ongoing basis until the communication is teared.
>
> I saw that the CURLINFO_LASTSOCKET is only used with CONNECT_ONLY, so I
am wondering if my above usage makes sense or wont work. I am currently
trying this scenario out but was wondering if this would work or not.
>
> Another question was in what thread context the CURLOPT_WRITEFUNCTION is
called.
>
> Is it curl's own thread context or the thread context in which function
was registered.
>
>
>
> Regards
> Mayank
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Received on 2012-09-07