void urlencode(char* dest, char* src) 
{

  int i;
  for(i = 0; i < strlen(src); i++) {
    char c = src[i];
    if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') ||
      (c >= '0' && c <= '9') ||
      c == '-' || c == '_' || c == '.' || c == '~') {
      char t[2];
      t[0] = c; 
      t[1] = '\0';
      strcat(dest, t);
    } 
    else {
      if(c == '/') {
        strcat(dest, "%252f");
      } 
      else {
        char t[4];
        snprintf(t, sizeof(t), "%%%02x", c & 0xff);
        strcat(dest, t);
      }
    }
  }
  
}