Node.js process.stderr.fd Property

The process.stderr.fd is an inbuilt application programming interface of class Process within process module which is used to returns the value of underlying file descriptor of process.stderr.

Syntax:

const process.stderr.fd

Parameters: This api takes no argument as a parameter.

Return Value: This api returns the value of the underlying file descriptor of process.stderr.

Example 1: 

index.js

// Node.js program to demonstrate the
// process.stderr.fd

// Importing process module
const process = require('process');

// Getting the value of file descriptor
// by using process.stderr.fd
const value = process.stderr.fd

// Display the result
console.log(value)

Run the index.js file using the following command:

node index.js

Output:

2

Example 2:

index.js

// Node.js program to demonstrate the
// process.stderr.fd

// Importing process module
const process = require('process');

// Updating file descriptor value
process.stderr.fd = 10

// Getting the value of file descriptor
// by using process.stderr.fd
const value = process.stderr.fd

// Display the result
console.log(value)

Run the index.js file using the following command:

node index.js

Output:

10

Reference: https://nodejs.org/dist/latest-v16.x/docs/api/process.html#process_process_stderr_fd