在文件结尾之后，seekg（）如何影响getline（）？

Question

如果我使用seekg()搜索文件末尾，std::getline()是否会更改传递给它的std::string？

//readWrite is an fstream object.
//fileLineLength is an int, every line in the file will be the same length.
string  RWDN::read(size_t number){
    string line = "";
    readWrite.seekg(number * fileLineLength);
    getline(readWrite, line);
    return line;
}

这会返回一些随机内容，还是line仍为空字符串？