source: bootcd/isolinux/syslinux-6.03/gnu-efi/gnu-efi-3.0/apps/t2.c

#include <efi.h>
#include <efilib.h>

EFI_STATUS
efi_main (EFI_HANDLE image, EFI_SYSTEM_TABLE *systab)
{
        SIMPLE_TEXT_OUTPUT_INTERFACE *conout;

        conout = systab->ConOut;
        uefi_call_wrapper(conout->OutputString, 2, conout, L"Hello World!\n\r");

        return EFI_SUCCESS;
}