Node.js stats.uid Property from fs.Stats Class

The stats.uid property is an inbuilt application programming interface of the fs.Stats class is used to get the numeric (number / bigint) identity of the user to which the file belongs to.

Syntax:

stats.uid;

Return Value: It returns a number or BigInt value which represents the identity of the user that owns the file.

Below examples illustrate the use of stats.uid property in Node.js:

Example 1:

// Node.js program to demonstrate the
// stats.uid property

// Accessing fs module
const fs = require('fs');

// Calling fs.Stats stats.uid
//for directory using stat
fs.stat('./', (err, stats) => {
  if (err) throw err;
  console.log("using stat: numeric "
    + "identity of the user is "
    + stats.uid);
});

//using lstat
fs.lstat('./', (err, stats) => {
  if (err) throw err;
  console.log("using lstat: numeric "
    + "identity of the user is "
    + stats.uid);
});

// For file
// Using stat
fs.stat('./filename.txt', (err, stats) => {
  if (err) throw err;
  console.log("using stat: numeric "
    + "identity of the user is "
    + stats.uid);
});

// Using lstat
fs.lstat('./filename.txt', (err, stats) => {
  if (err) throw err;
  console.log("using lstat: numeric identity"
    + " of the user is  "+stats.uid);
});

Output:

using stat: numeric identity of the user is  9932440
using lstat: numeric identity of the user is  9932440
using stat: numeric identity of the user is  9932440
using lstat: numeric identity of the user is  9932440

Example 2:

// Node.js program to demonstrate the
// stats.uid property

// Accessing fs module
const fs = require('fs').promises;

// Calling fs.Stats stats.uid
(async() => {
    const stats = await fs.stat('./filename.txt');
  console.log("using stat synchronous: numeric "
    + "identity of the user is  "+stats.uid);
})().catch(console.error)

Output:

(node:14456) ExperimentalWarning: The fs.promises API 
is experimental 
using stat synchronous: numeric identity of the user is 9932440

Note: The above program will compile and run by using the node filename.js command and use the file_path correctly. This API will work correctly for POSIX system. In other systems like WINDOWS it will return 0.

Reference: https://nodejs.org/api/fs.html#fs_stats_uid