I have a Function in an unmanaged Dll which expects a pointer to a Handle like that example:
extern "C" __declspec(dllexport) BOOL __stdcall MySetEvent(HANDLE* handle,
int size)
{
if (!handle) return FALSE;
assert(sizeof(*handle) == size);
printf("MySetEvent(%p, %d)\n", *handle, size);
return SetEvent(*handle);
}
How I can call this from C# without using DangerousGetHandle like in that example?
[DllImport("UnmanagedDll", SetLastError = true)]
static extern int MySetEvent(ref IntPtr handle, int size);
AutoResetEvent ev = new AutoResetEvent(false);
var handle = ev.SafeWaitHandle.DangerousGetHandle();
MySetEvent(ref handle, Marshal.SizeOf(handle));
This doesn't work (a MissingMethodException for .ctor is thrown):
[DllImport("UnmanagedDll", SetLastError = true)]
static extern int MySetEvent([In] ref SafeHandle handle, int size);
SafeHandle handle = ev.SafeWaitHandle;
MySetEvent(ref handle, Marshal.SizeOf(IntPtr.Zero));