**************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
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*
* Copyright (C) 2021, Max Dymond, <max.dymond@microsoft.com>, et al.
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* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
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**************************************************************************

CURLOPT_PREREQDATA - pointer passed to the pre-request callback #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PREREQDATA, void *pointer); Pass a pointer that will be untouched by libcurl and passed as the first argument in the pre-request callback set with CURLOPT_PREREQFUNCTION(3). NULL All

static int prereq_callback(void *clientp,
 char *conn_primary_ip,
 char *conn_local_ip,
 int conn_primary_port,
 int conn_local_port)
{
 printf("Connection made to %s:%s\\n", conn_primary_ip, conn_primary_port);
 return CURL_PREREQFUNC_OK;
}

{
 struct data prereq_data;
 curl_easy_setopt(CURL *handle, CURLOPT_PREREQFUNCTION, prereq_callback);
 curl_easy_setopt(CURL *handle, CURLOPT_PREREQDATA, &prereq_data);
}

Added in 7.80.0 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. CURLOPT_PREREQFUNCTION "(3) "