file1.js

var exec = require('child_process').exec;

	function wew(cb){
		exec("iwlist wlan2 scan|grep -Po '(?<=Address: )\\S+|(?<=Signal level=)\\S+|(?<=ESSID:\")[^\"]+'", test(cb));
	}
	
	function test(cb) {
		return function (error, stdout, stderr) {
			var out = stdout.replace(/^\s+/mg, '');
			out = out.split('\n');
			var cells = [];
			var line;
			var info = {};
		 
			for (var i=0,l=out.length-1,m=1; i<l; i++,m++) {
				line = out[i];
				if(i%3 == 0 && i!=0){
					cells.push(info);
					info = {};
				}
				 
				if(m%3==1)		{ 	info['mac'] = line; 	}
				else if(m%3==2)	{ 	info['signal'] = line; 	}
				else if(m%3==0)	{	info['essid'] = line; 	}
			}
			cells.push(info);
			// console.log(cells);
			for (var i in cells) {
			//  console.log("the array: " + cells[i].mac); //"aa", bb", "cc"
			}
			
			
			cb(cells);
		}
	}
		
exports.command = wew;

main.js

var reader = require( './file1.js' );
reader.command(function (bang) {
  console.log(bang);
});