https://nalar.dev/tags/filesystems/ Recent content in Filesystems on Nalar Hugo en-us Fri, 04 Sep 2026 00:00:00 +0700 https://nalar.dev/write-files-atomically-on-linux-with-rename-and-fsync/ Fri, 04 Sep 2026 00:00:00 +0700 https://nalar.dev/write-files-atomically-on-linux-with-rename-and-fsync/ <p>Updating a small file looks simple: open it, truncate it, write the new contents, and close it. That works when nothing interrupts the write.</p> <p>The failure mode appears when a process crashes, the machine loses power, or another process reads the file while it is being rewritten. A reader can observe an empty or partially written file, and a crash can leave the pathname referring to incomplete data.</p> <p>For configuration files, state snapshots, generated metadata, and similar single-file updates, a better pattern is to write a complete replacement beside the original file and then rename it into place.</p>