Executing external command with Swift

external_command.swift

import Foundation

func executeCommand(command: String, args: [String]) -> String {
    
    let task = NSTask()
    
    task.launchPath = command
    task.arguments = args
    
    let pipe = NSPipe()
    task.standardOutput = pipe
    task.launch()
    
    let data = pipe.fileHandleForReading.readDataToEndOfFile()
    let output: String = String(data: data, encoding: NSUTF8StringEncoding)!
    
    return output
}

let commandOutput = executeCommand("/usr/sbin/arp", args: ["-a"])
print("Command output: \(commandOutput)")