Add mutex syscalls

init/init.c

@@ -9,17 +9,21 @@
 #define EXAMPLE 1
 
 #if EXAMPLE == 1
-void app_main (void) {
-  test ('a');
-  test ('a');
-  test ('a');
 
-  int* xs = malloc (1024 * sizeof (*xs));
-  memset (xs, 123, 1024 * sizeof (*xs));
-  free (xs);
-
-  test ('a');
-  test ('a');
-  test ('a');
+void app_thread1 (void) {
+  test ('b');
+  quit ();
 }
+
+int spawn (void (*fn) (void)) {
+  size_t stack_size = 256 * PAGE_SIZE;
+  void* stack = malloc (stack_size);
+  if (stack == NULL)
+    return -ST_OOM_ERROR;
+
+  uintptr_t stack_top = (uintptr_t)stack + stack_size;
+  return clone (stack_top, stack_size, fn);
+}
+
+void app_main (void) { spawn (&app_thread1); }
 #endif