microhttpd使用的代碼，接受客戶客戶端post的數據，然後在響應

#include <sys/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <microhttpd.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#define PORT 8888


static int
print_out_key (void *cls, enum MHD_ValueKind kind, const char *key,
               const char *value)
{
  printf ("%s: %s\n", key, value);
  return MHD_YES;
}

static int
answer_to_connection (void *cls, struct MHD_Connection *connection,
                      const char *url, const char *method,
                      const char *version, const char *upload_data,
                      size_t *upload_data_size, void **con_cls)
{

    //接受參數
  printf("----------------------------------new line------------------------------------------\n");
  printf ("New %s request for %s using version %s\n", method, url, version);

  MHD_get_connection_values (connection, MHD_HEADER_KIND, print_out_key,
                             NULL);
 
  const char* body = MHD_lookup_connection_value (connection, MHD_POSTDATA_KIND, NULL); 
  if (body == NULL) 
      return 0; 
  printf("----------------------------------post date-------------------------------------------\n");
  printf("body = %s\n" , body);
  //應答
  const char *page = "0";
  struct MHD_Response *response;
  int ret;
  
  response =
    MHD_create_response_from_buffer (strlen (page), (void *) page, 
                     MHD_RESPMEM_MUST_COPY);
  ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
  return ret;
}

int
main ()
{
  struct MHD_Daemon *daemon;

  daemon = MHD_start_daemon (MHD_USE_SELECT_INTERNALLY, PORT, NULL, NULL,
                             &answer_to_connection, NULL, MHD_OPTION_END);
  if (NULL == daemon)
    return 1;

  getchar ();

  MHD_stop_daemon (daemon);
  return 0;
}