winnativeapi.c

#include <winternl.h>
#include <Windows.h> // includes GetStdHandle()
#include <string.h>
// #include <stdio.h>

typedef VOID (NTAPI *PIO_APC_ROUTINE)(PVOID ApcContext, PIO_STATUS_BLOCK IoStatusBlock, ULONG Reserved);

typedef NTSTATUS (NTAPI *NtWriteFile_t)(HANDLE FileHandle, HANDLE Event, PIO_APC_ROUTINE ApcRoutine,
    PVOID ApcContext, PIO_STATUS_BLOCK IoStatusBlock, PVOID Buffer, ULONG Length,
    PLARGE_INTEGER ByteOffset, PULONG Key);

static NtWriteFile_t write_file = NULL;

int main(void)
{
    HANDLE stdOut = GetStdHandle(STD_OUTPUT_HANDLE);
    IO_STATUS_BLOCK ioStatus;

    const char *str = "Hello, world!\n";
    size_t len = strlen(str);
    // printf("%s", str);
    // WriteConsoleA(stdOut, str, len, NULL, NULL);
    // WriteFile(stdOut, str, len, NULL, NULL);

    *(void **)(&write_file) = GetProcAddress(GetModuleHandleA("ntdll.dll"), "NtWriteFile");
    write_file(stdOut, NULL, NULL, NULL, &ioStatus, (PVOID) str, len, NULL, NULL);

    return 0;
}