Hi all, The code below is a test for the CURL C API . The problem is that the callback function write_callback is never called. Why ?

/** compilation: g++ source.cpp -lcurl */

#include <assert.h>
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cassert>
#include <curl/curl.h>

using namespace std;

static size_t write_callback(void *ptr, size_t size, size_t nmemb, void *userp)
    {
    std::cerr << "CALLBACK WAS CALLED" << endl;
    exit(-1);
    return size*nmemb;
    }

static void test_curl()
    {
    int any_data=1;
    CURLM* multi_handle=NULL;
        CURL* handle_curl = ::curl_easy_init();
    assert(handle_curl!=NULL);
        ::curl_easy_setopt(handle_curl, CURLOPT_URL, "http://en.wikipedia.org/wiki/Main_Page");
        ::curl_easy_setopt(handle_curl, CURLOPT_WRITEDATA, &any_data);
        ::curl_easy_setopt(handle_curl, CURLOPT_VERBOSE, 1);
        ::curl_easy_setopt(handle_curl, CURLOPT_WRITEFUNCTION, write_callback);
    ::curl_easy_setopt(handle_curl, CURLOPT_USERAGENT, "libcurl-agent/1.0");

        multi_handle = ::curl_multi_init();
    assert(multi_handle!=NULL);
        ::curl_multi_add_handle(multi_handle, handle_curl);
    int still_running=0;
        /* lets start the fetch */
        while(::curl_multi_perform(multi_handle, &still_running) ==
              CURLM_CALL_MULTI_PERFORM );
        std::cerr << "End of curl_multi_perform."<< endl;
        //cleanup should go here
        ::exit(EXIT_SUCCESS);
    }

int main(int argc,char** argv)
    {
    test_curl();
    return 0;
    }

Many thanks

Pierre