Pretty print a json skipping the BOM if present

pp_json_bom.js

#!/usr/bin/env node

var fs = require('fs');

var prettyPrint = function(json) {
    return JSON.stringify(JSON.parse(json), null, '  ');
};

var args = process.argv.slice(2);
if (args.length == 0 || args.length > 1) {
  console.log("Invalid args number: pp_json_bon FILE");
  process.exit(1);
}

filename = args[0];
fs.readFile(filename, function(error, buffer) {
    if (error) {
        console.error(error);
        return;
    }

    var bom = new Buffer(3);
    buffer.copy(bom, 0);

    if (bom.equals(new Buffer([0xef, 0xbb, 0xbf]))) {
        console.log(prettyPrint(buffer.slice(3)));
    }
    else {
        console.log(prettyPrint(buffer));
    }
});