README files play an important role in providing installation-related instructions to software users and are widely used in open source software systems on platforms such as GitHub. However, these files often suffer from various documentation issues, leading to challenges in comprehension and potential errors in content. Despite their significance, there is a lack of systematic understanding regarding the documentation efforts invested in README files, especially in the context of installation-related instructions, which are crucial for users to start with a software project. To fill the research gap, we conducted a qualitative study, investigating 400 GitHub repositories with 1,163 README commits that focused on updates in installation-related sections. Our research revealed six major categories of changes in the README commits, namely pre-installation instructions, installation instructions, post-installation instructions, help information updates, document presentation, and external resource management. We further provide detailed insights into modification behaviours and offer examples of these updates. Based on our findings, we provide recommendations to practitioners for maintaining their README files, as well as motivations for future research directions. These recommendations and research directions encompass completeness, correctness and up-to-dateness, and information presentation consideration. The proposed research directions span the development of automated documentation tools and empirical studies to enhance comprehension of the needs of documentation users. Furthermore, we provide a comprehensive README template tailored to cover the installation-related sections for document maintainers, serving as a practical starting point for their efforts.

翻译：README文件在向软件用户提供安装相关指令方面发挥着重要作用，广泛应用于GitHub等平台的开源软件系统。然而，这些文件常存在各类文档问题，导致理解困难并可能引发内容错误。尽管其重要性不言而喻，但学界对README文件的文档编制投入——尤其是与安装相关指令（用户使用软件项目的关键环节）的系统性理解仍存在空白。为填补这一研究空白，我们开展了定性研究，对400个GitHub仓库中涉及安装章节更新的1,163条README提交记录进行了分析。研究揭示了README提交中的六大变更类别：预安装指令、安装指令、后安装指令、帮助信息更新、文档呈现方式及外部资源管理。我们进一步提供了修改行为的详细洞见，并给出这些更新的示例。基于研究发现，我们为开发者维护README文件提出了实践建议，并为未来研究方向提供了动因。这些建议与研究方向涵盖：完整性、正确性、时效性及信息呈现考量。提议的研究方向包括开发自动化文档工具和开展实证研究以增强对文档用户需求的理解。此外，我们为文档维护者提供了涵盖安装相关章节的综合性README模板，作为其工作的实用起点。