[util.cpp#L216](https://github.com/bitcoin/bitcoin/blob/master/src/util.cpp#L216) 
if `fopen `failed, a null file pointer could be passed to `FileWriteStr(vMsgsBeforeOpenLog->front(), fileout);`
{
    boost::filesystem::ifstream streamConfig(GetConfigFile(confPath));
    if (!streamConfig.good())
        return; 
    {
        LOCK(cs_args);
        set<string> setOptions;
        setOptions.insert("*");
        for (boost::program_options::detail::config_file_iterator it(streamConfig, setOptions), end; it != end; ++it)
        {
            
            string strKey = string("-") + it->string_key;
            string strValue = it->value[0];
            InterpretNegativeSetting(strKey, strValue);
            if (mapArgs.count(strKey) == 0)
                mapArgs[strKey] = strValue;
            _mapMultiArgs[strKey].push_back(strValue);
        }
    }
    
    ClearDatadirCache();
}
#ifndef WIN32
boost::filesystem::path GetPidFile()