Better user programs with a special std. Sleep and exit are calling scheduler instead of wfi.

crates/os-std/src/lib.rs

@@ -0,0 +1,21 @@
+#![no_std]
+
+mod prelude;
+
+pub use shared::syscall;
+
+#[macro_export]
+macro_rules! custom_std_setup {
+    () => {
+        #[panic_handler]
+        fn panic(_panic_info: &core::panic::PanicInfo) -> ! {
+            // TODO print
+            loop {}
+        }
+
+        #[unsafe(no_mangle)]
+        pub extern "C" fn _start() {
+            main()
+        }
+    };
+}

crates/os-std/src/prelude.rs

@@ -0,0 +1 @@
+