入力を待ち受けつつバックグラウンドで定期処理

00_SPEC.mkdn

仕様

1. 文字列 Hoge, Fuga, Hago を 3秒置きに順に表示する
2. 処理1を無限ループさせ，バックグラウンド処理にする
3. ユーザの入力を待ち受けて，入力内容をそのまま出力する

loop_iterator_wait.js

var messages = ['Hoge', 'Fuga', 'Hago'];
var interval = 3000;
var i = 0;
var last = messages.length - 1;
var loop = function() {
    console.log(messages[i]);
    i == last ? i = 0 : i++;
    setTimeout(loop, interval);
};
loop();

do {
  input = prompt();
  console.log(input);
} while (input);

loop_iterator_wait.lua

#!/usr/bin/env lua

-- うまくいってない
loop = coroutine.create(
    function() 
        local messages = {'Hoge', 'Fuga', 'Hago'}
        while true do
            for k, v in pairs(messages) do
                print(v)
            end
        end
    end
)

interval = 3
while true do 
    local start = os.time()
    coroutine.resume(loop)
    repeat print(io.read()) until os.time() < start + interval
end

loop_iterator_wait.php

<?php
/* Clean (erase) the output buffer and turn off output buffering */
ob_end_clean();

/* うまくいってない */
$messages = array('Hoge', 'Fuga', 'Hago');
$interval = 3;
while (true) {
    foreach ($messages as $v) {
        echo $v . PHP_EOL;
        sleep($interval);
    }
}

while ($line = trim(fgets(STDIN))) {
    echo $line . PHP_EOL;
}

loop_iterator_wait.pl

#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;

use Thread qw(async);

async {
    my @messages = qw(Hoge Fuga Hago);
    my $interval = 3;
    while () {
        foreach my $v (@messages) {
            say $v;
            sleep $interval;
        }
    }
};
 
print while (<>);

loop_iterator_wait.ps1

Start-Job {
    $messages = ('Hoge', 'Fuga', 'Hago')
    $interval = 3
    while (1) {
        foreach ($v in $messages) {
            $v | Out-File $HOME\messages.txt -append
            sleep $interval
        }
    }
}

while (1) {
    Read-Host | Out-Host
}

loop_iterator_wait.py

#!/usr/bin/env python

import threading
import time

def loop():
    messages = ['Hoge', 'Fuga', 'Hago']
    interval = 3
    while True:
        for v in messages:
            print v
            time.sleep(interval)

t = threading.Thread(target=loop)
t.setDaemon(True)
t.start()

while True:
    print raw_input()

loop_iterator_wait.rb

#!/usr/bin/env ruby

Thread.start do
  messages = %w[Hoge Fuga Hago]
  interval = 3
  loop do
    messages.each do |v|
      puts v
      sleep interval;
    end
  end
end

puts $_ while gets

loop_iterator_wait.scala

import scala.concurrent.ops._
import java.lang.Thread._

spawn {
    val messages = List("Hoge", "Fuga", "Hago")
    val interval = 3000
    while (true) {
        for (v <- messages) {
            println(v)
            sleep(interval)
        }
    }
}

do println(readLine) while (true) 

loop_iterator_wait.sh

#!/bin/bash

LOOP=`cat << 'EOL'
    MESSAGES=(Hoge Fuga Hago)
    INTERVAL=3
    while :; do
        for v in ${MESSAGES[@]}; do
            PARENT=\`pgrep -P $PPID\`
            if [ ! "$PARENT" ]; then
                exit 9
            fi
            echo $v
            sleep $INTERVAL
        done
    done
EOL`
bash -c "$LOOP" &

while read INPUT; do
    echo $INPUT
done