title: curl_easy_getinfo undefined symbol error
body: <p>I am using asterisk version 13.5.0. In utils directory, I created a new module called curl_util with source code as below: </p>
  
  <pre><code>#include "asterisk/curl_utils.h"
  HttpResponse * httpResponseNew()
  {
      HttpResponse * response = calloc(1, sizeof(HttpResponse));
  
      return response;
  error:
      return NULL;
  }
  
  HttpResponse * httpRequestPost(char *url, char *post_body, size_t size)
  {
      struct MemoryStruct chunk;
      CURL *curl = curl_easy_init();
  
      chunk.memory = malloc(1);
      chunk.size = 0;
  
      HttpResponse *response = httpResponseNew();
      curl_easy_setopt(curl, CURLOPT_URL, url);
      curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
      curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
      curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 0);
      curl_easy_setopt(curl, CURLOPT_POST, 1L);
      curl_easy_setopt(curl, CURLOPT_POSTFIELDS, post_body);
      curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, size);
      curl_easy_setopt(curl, CURLOPT_TIMEOUT, 30);
      curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
      curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, HttpResponseMemoryWriter);
      curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&amp;chunk);
  
      response-&gt;res = curl_easy_perform(curl);
  
      if (response-&gt;res != CURLE_OK)
      {
          response-&gt;OK = 0;
      }
      else
      {
          response-&gt;OK = 1;
          response-&gt;size = chunk.size;
          response-&gt;body = chunk.memory;
      }
  
      curl_easy_cleanup(curl);
  
      return response;
  
  error:
      free(chunk.memory);
      if (curl) curl_easy_cleanup(curl);
      return response;
  }
  </code></pre>
  
  <p>In chan_sip.c, I call above mentioned httpRequestPost function.
  Executing make and make install are OK. 
  But, when starting dahdi and asterisk, I got the following error:</p>
  
  <p>Error loading module chan_sip.so: undefined symbol: httpRequestPost </p>
  
  <p>loader.c: module chan_sip.so could not be loaded.</p>
  
  <p>Could you please give hints or advices to fix this error?
  Thank you in advance.</p>