const process.allowedNodeEnvironmentFlags

// Node.js program to demonstrate the   
// Process.allowedNodeEnvironmentFlags Property 
  
// Importing process module 
const process = require('process'); 
  
// Getting NodeEnvironmentFlags 
const flags = process.allowedNodeEnvironmentFlags; 
  
// Display the total size 
console.log(flags.size) 

node index.js

104

// Node.js program to demonstrate the   
// Process.allowedNodeEnvironmentFlags Property 
  
// Importing process module 
const process = require('process'); 
  
// Getting NodeEnvironmentFlags 
process.allowedNodeEnvironmentFlags.forEach((flag) => { 
  
    // Display the length for each 
    console.log("Flag: ", flag, ", Length: ", flag.length) 
});

node index.js

Flag:  --icu-data-dir , Length:  14
Flag:  --title , Length:  7
..
..

..

..
Flag:  --loader , Length:  8
Flag:  -r , Length:  2