NSIS/Contrib/ExDLL/exdll.c

#include <windows.h>
#include <pluginapi.h> // nsis plugin

HINSTANCE g_hInstance;

HWND g_hwndParent;

void __declspec(dllexport) myFunction(HWND hwndParent, int string_size, 
                                      char *variables, stack_t **stacktop,
                                      extra_parameters *extra)
{
  g_hwndParent=hwndParent;

  EXDLL_INIT();


  // note if you want parameters from the stack, pop them off in order.
  // i.e. if you are called via exdll::myFunction file.dat poop.dat
  // calling popstring() the first time would give you file.dat,
  // and the second time would give you poop.dat. 
  // you should empty the stack of your parameters, and ONLY your
  // parameters.

  // do your stuff here
  {
    char buf[1024];
    wsprintf(buf,"$0=%s\n",getuservariable(INST_0));
    MessageBox(g_hwndParent,buf,0,MB_OK);
  }
}



BOOL WINAPI DllMain(HANDLE hInst, ULONG ul_reason_for_call, LPVOID lpReserved)
{
  g_hInstance=hInst;
	return TRUE;
}