From c5e7524b89a780fcc07badad94328fc486184252 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andreas=20M=C3=B6ller?= <am@localheinz.com>
Date: Mon, 23 Jul 2018 08:43:26 +0200
Subject: [PATCH] Enhancement: Add example for tailing a log file

---
 examples/tail.php | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 examples/tail.php

diff --git a/examples/tail.php b/examples/tail.php
new file mode 100644
index 00000000..a790414b
--- /dev/null
+++ b/examples/tail.php
@@ -0,0 +1,40 @@
+<?php
+
+require dirname(__DIR__) . '/vendor/autoload.php';
+
+$loop = \React\EventLoop\Factory::create();
+
+$filesystem = \React\Filesystem\Filesystem::create($loop);
+
+$path = '/var/log/access.log';
+
+$filesystem->getContents($path)->then(function ($content) use ($loop, $filesystem, $path) {
+    echo $content;
+
+    $lastSize = strlen($content);
+
+    $file = $filesystem->file($path);
+
+    $file->open('r')->then(function (\React\Stream\ReadableStreamInterface $stream) use ($filesystem, $loop, $file, &$lastSize) {
+        /** @var \React\Filesystem\Stream\GenericStreamInterface $stream */
+        $fileDescriptor = $stream->getFiledescriptor();
+
+        $adapter = $filesystem->getAdapter();
+
+        $loop->addPeriodicTimer(1, function () use ($adapter, $fileDescriptor, $file, &$lastSize) {
+            $file->size()->then(function ($size) use ($adapter, $fileDescriptor, &$lastSize) {
+                if ($lastSize === $size) {
+                    return;
+                }
+
+                $adapter->read($fileDescriptor, $size - $lastSize, $lastSize)->then(function ($content) {
+                    echo $content;
+                });
+
+                $lastSize = $size;
+            });
+        });
+    });
+});
+
+$loop->run();