test dll

#include <windows.h>

void NTAPI tls_callback(PVOID hModule, DWORD reason, PVOID reserved)
{
    if (reason == DLL_PROCESS_ATTACH)
        MessageBoxA(NULL, "TLS callback fired", "TLS", MB_OK);
}

// Tell the linker to place `tls_callback` into the TLS callback table
#ifdef _MSC_VER
#pragma const_seg(".CRT$XLB")
EXTERN_C const PIMAGE_TLS_CALLBACK pTlsCallback = tls_callback;
#pragma const_seg()
#else
PIMAGE_TLS_CALLBACK __attribute__((section(".CRT$XLB"))) pTlsCallback = tls_callback;
#endif

BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
{
    if (fdwReason == DLL_PROCESS_ATTACH)
    {
        MessageBoxA(NULL, "DllMain fired", "DLL", MB_OK);
    }
    return TRUE;
}