More examples and tweaks

* Signal dispatch() method now uses own pid as default value
* SharedData now updates checksum cache on set()

examples/locks.php

@@ -0,0 +1,43 @@
+<?php
+
+require_once __DIR__."/../vendor/autoload.php";
+
+use NoccyLabs\Ipc\Lock\FileLock;
+
+// Creating the lock will not acquire it
+$lock1 = new FileLock(__FILE__);
+$lock2 = new FileLock(__FILE__);
+
+// Acquire the lock like this
+if ($lock1->acquire()) {
+    echo "lock1 acquired\n";
+} else {
+    echo "lock1 not acquired\n";
+}
+
+// Test the locks like this
+if ($lock1->isLocked()) {
+    echo "lock1 is locked\n";
+} else {
+    echo "lock1 is not locked\n";
+}
+if ($lock2->isLocked()) {
+    echo "lock2 is locked\n";
+} else {
+    echo "lock2 is not locked\n";
+}
+
+// This will timeout after a second
+if ($lock2->acquire(1)) {
+    echo "lock2 acquired\n";
+} else {
+    echo "lock2 not acquired\n";
+}
+
+// After releasing, you can acquire it
+$lock1->release();
+if ($lock2->acquire(1)) {
+    echo "lock2 acquired\n";
+} else {
+    echo "lock2 not acquired\n";
+}