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diff --git a/vendor/r-efi/examples/hello-world.rs b/vendor/r-efi/examples/hello-world.rs
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+// Example: Hello World!
+//
+// This is an example UEFI application that prints "Hello World!", then waits
+// for key input before it exits. It serves as base example how to write UEFI
+// applications without any helper modules other than the UEFI protocol
+// definitions.
+//
+// This example builds upon the `freestanding.rs` example, using the same setup
+// and rust integration. See there for details on the panic-handler and entry
+// point configuration.
+//
+// Note that UEFI uses UTF-16 strings. Since rust literals are UTF-8, we have
+// to use an open-coded, zero-terminated, UTF-16 array as argument to
+// `output_string()`. Similarly to the panic handler, real applications should
+// rather use UTF-16 modules.
+
+#![no_main]
+#![no_std]
+
+use r_efi::efi;
+
+#[panic_handler]
+fn panic_handler(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[export_name = "efi_main"]
+pub extern "C" fn main(_h: efi::Handle, st: *mut efi::SystemTable) -> efi::Status {
+    let s = [
+        0x0048u16, 0x0065u16, 0x006cu16, 0x006cu16, 0x006fu16, // "Hello"
+        0x0020u16, //                                             " "
+        0x0057u16, 0x006fu16, 0x0072u16, 0x006cu16, 0x0064u16, // "World"
+        0x0021u16, //                                             "!"
+        0x000au16, //                                             "\n"
+        0x0000u16, //                                             NUL
+    ];
+
+    // Print "Hello World!".
+    let r =
+        unsafe { ((*(*st).con_out).output_string)((*st).con_out, s.as_ptr() as *mut efi::Char16) };
+    if r.is_error() {
+        return r;
+    }
+
+    // Wait for key input, by waiting on the `wait_for_key` event hook.
+    let r = unsafe {
+        let mut x: usize = 0;
+        ((*(*st).boot_services).wait_for_event)(1, &mut (*(*st).con_in).wait_for_key, &mut x)
+    };
+    if r.is_error() {
+        return r;
+    }
+
+    efi::Status::SUCCESS
+}