All 15 File System & File Processing questions
More in File System & File Processing
What is the difference between fs.unlink() and fs.rmdir() (or the newer fs.rm()) in Node.js? How would you recursively read all files within a directory tree in Node.js? How would you safely check if a file exists in Node.js before attempting to read it, avoiding a race condition? What is the difference between fs.appendFile() and opening a file with the 'a' flag and writing to it manually? How would you copy a large file efficiently in Node.js, and what's the difference between fs.copyFile() and manually piping streams? What is the purpose of the 'flag' option in fs.writeFile(), and what's the difference between 'w', 'a', and 'wx' flags? How would you implement a file-watching feature in Node.js using fs.watch(), and what are its known cross-platform limitations? How would you implement atomic file writes in Node.js to avoid leaving a file in a corrupted, half-written state if the process crashes mid-write? How would you process a very large CSV file in Node.js without loading the entire file into memory? How would you implement file locking in Node.js to prevent two processes from writing to the same file simultaneously?
Advertisement
Back to results for “Advanced Node.js”
Node.js › File System & File Processing

What is the difference between fs.stat() and fs.lstat(), and when does the distinction matter?

Intermediate

Answer

fs.stat() returns file information, automatically following symbolic links to report on the actual target file they point to. fs.lstat() returns information about the symbolic link itself (its size, type) rather than the file it points to -- the distinction matters specifically when working with symlinks and you need to know whether a given path is itself a symlink, rather than transparently resolving through it to whatever it points to.
const fs = require('node:fs/promises');

const stats = await fs.lstat('shortcut.txt');
if (stats.isSymbolicLink()) {
  const target = await fs.readlink('shortcut.txt');
  console.log('This is a symlink pointing to:', target);
}
Real-world example A file-organization tool that needs to detect and specifically handle symbolic links (rather than silently following them, which could create infinite loops with circular symlinks) uses fs.lstat() to identify symlinks before deciding how to process them.

Common follow-ups: What specific problem, like an infinite loop, could occur if a file-tree-walking tool doesn't account for symbolic links at all?;What information does fs.Stats provide beyond just file size and type, like timestamps?

CLI Tools & Scripting with Node.js;Advanced Node.js
All 15 File System & File Processing questions