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diff --git a/docs/examples/web/physac/pthread-main.js b/docs/examples/web/physac/pthread-main.js
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+++ b/docs/examples/web/physac/pthread-main.js
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+// Pthread Web Worker startup routine:
+// This is the entry point file that is loaded first by each Web Worker
+// that executes pthreads on the Emscripten application.
+
+// Thread-local:
+var threadInfoStruct = 0; // Info area for this thread in Emscripten HEAP (shared). If zero, this worker is not currently hosting an executing pthread.
+var selfThreadId = 0; // The ID of this thread. 0 if not hosting a pthread.
+var parentThreadId = 0; // The ID of the parent pthread that launched this thread.
+var tempDoublePtr = 0; // A temporary memory area for global float and double marshalling operations.
+
+// Thread-local: Each thread has its own allocated stack space.
+var STACK_BASE = 0;
+var STACKTOP = 0;
+var STACK_MAX = 0;
+
+// These are system-wide memory area parameters that are set at main runtime startup in main thread, and stay constant throughout the application.
+var buffer; // All pthreads share the same Emscripten HEAP as SharedArrayBuffer with the main execution thread.
+var DYNAMICTOP_PTR = 0;
+var TOTAL_MEMORY = 0;
+var STATICTOP = 0;
+var staticSealed = true; // When threads are being initialized, the static memory area has been already sealed a long time ago.
+var DYNAMIC_BASE = 0;
+
+var ENVIRONMENT_IS_PTHREAD = true;
+
+// Cannot use console.log or console.error in a web worker, since that would risk a browser deadlock! https://bugzilla.mozilla.org/show_bug.cgi?id=1049091
+// Therefore implement custom logging facility for threads running in a worker, which queue the messages to main thread to print.
+var Module = {};
+
+function threadPrint() {
+  var text = Array.prototype.slice.call(arguments).join(' ');
+  console.log(text);
+}
+function threadPrintErr() {
+  var text = Array.prototype.slice.call(arguments).join(' ');
+  console.error(text);
+}
+function threadAlert() {
+  var text = Array.prototype.slice.call(arguments).join(' ');
+  postMessage({cmd: 'alert', text: text, threadId: selfThreadId});
+}
+Module['print'] = threadPrint;
+Module['printErr'] = threadPrintErr;
+this.alert = threadAlert;
+
+this.onmessage = function(e) {
+  if (e.data.cmd === 'load') { // Preload command that is called once per worker to parse and load the Emscripten code.
+    // Initialize the thread-local field(s):
+    tempDoublePtr = e.data.tempDoublePtr;
+
+    // Initialize the global "process"-wide fields:
+    buffer = e.data.buffer;
+    Module['TOTAL_MEMORY'] = TOTAL_MEMORY = e.data.TOTAL_MEMORY;
+    STATICTOP = e.data.STATICTOP;
+    DYNAMIC_BASE = e.data.DYNAMIC_BASE;
+    DYNAMICTOP_PTR = e.data.DYNAMICTOP_PTR;
+
+    PthreadWorkerInit = e.data.PthreadWorkerInit;
+    importScripts(e.data.url);
+    if (typeof FS !== 'undefined') FS.createStandardStreams();
+    postMessage({ cmd: 'loaded' });
+  } else if (e.data.cmd === 'objectTransfer') {
+    PThread.receiveObjectTransfer(e.data);
+  } else if (e.data.cmd === 'run') { // This worker was idle, and now should start executing its pthread entry point.
+    threadInfoStruct = e.data.threadInfoStruct;
+    __register_pthread_ptr(threadInfoStruct, /*isMainBrowserThread=*/0, /*isMainRuntimeThread=*/0); // Pass the thread address inside the asm.js scope to store it for fast access that avoids the need for a FFI out.
+    assert(threadInfoStruct);
+    selfThreadId = e.data.selfThreadId;
+    parentThreadId = e.data.parentThreadId;
+    assert(selfThreadId);
+    assert(parentThreadId);
+    // TODO: Emscripten runtime has these variables twice(!), once outside the asm.js module, and a second time inside the asm.js module.
+    //       Review why that is? Can those get out of sync?
+    STACK_BASE = STACKTOP = e.data.stackBase;
+    STACK_MAX = STACK_BASE + e.data.stackSize;
+    assert(STACK_BASE != 0);
+    assert(STACK_MAX > STACK_BASE);
+    Runtime.establishStackSpace(e.data.stackBase, e.data.stackBase + e.data.stackSize);
+    var result = 0;
+
+    PThread.receiveObjectTransfer(e.data);
+
+    PThread.setThreadStatus(_pthread_self(), 1/*EM_THREAD_STATUS_RUNNING*/);
+
+    try {
+      // HACK: Some code in the wild has instead signatures of form 'void *ThreadMain()', which seems to be ok in native code.
+      // To emulate supporting both in test suites, use the following form. This is brittle!
+      if (typeof asm['dynCall_ii'] !== 'undefined') {
+        result = asm.dynCall_ii(e.data.start_routine, e.data.arg); // pthread entry points are always of signature 'void *ThreadMain(void *arg)'
+      } else {
+        result = asm.dynCall_i(e.data.start_routine); // as a hack, try signature 'i' as fallback.
+      }
+    } catch(e) {
+      if (e === 'Canceled!') {
+        PThread.threadCancel();
+        return;
+      } else {
+        Atomics.store(HEAPU32, (threadInfoStruct + 4 /*{{{ C_STRUCTS.pthread.threadExitCode }}}*/ ) >> 2, -2 /*A custom entry specific to Emscripten denoting that the thread crashed.*/);
+        Atomics.store(HEAPU32, (threadInfoStruct + 0 /*{{{ C_STRUCTS.pthread.threadStatus }}}*/ ) >> 2, 1); // Mark the thread as no longer running.
+        _emscripten_futex_wake(threadInfoStruct + 0 /*{{{ C_STRUCTS.pthread.threadStatus }}}*/, 0x7FFFFFFF/*INT_MAX*/); // wake all threads
+        throw e;
+      }
+    }
+    // The thread might have finished without calling pthread_exit(). If so, then perform the exit operation ourselves.
+    // (This is a no-op if explicit pthread_exit() had been called prior.)
+    if (!Module['noExitRuntime']) PThread.threadExit(result);
+    else console.log('pthread noExitRuntime: not quitting.');
+  } else if (e.data.cmd === 'cancel') { // Main thread is asking for a pthread_cancel() on this thread.
+    if (threadInfoStruct && PThread.thisThreadCancelState == 0/*PTHREAD_CANCEL_ENABLE*/) {
+      PThread.threadCancel();
+    }
+  } else {
+    Module['printErr']('pthread-main.js received unknown command ' + e.data.cmd);
+  }
+}