::(作用域解释符)前什么都没有,这又是怎么回事?
我这里有一段代码,
来自Microsoft Visual Studio\VC98\MFC\SRC\THRDCORE.CPP
do
{
// pump message, but quit on WM_QUIT
if (!PumpMessage())
return ExitInstance();
// reset "no idle" state after pumping "normal" message
if (IsIdleMessage(&m_msgCur))
{
bIdle = TRUE;
lIdleCount = 0;
}
} while (::PeekMessage(&m_msgCur, NULL, NULL, NULL, PM_NOREMOVE));
其中while (::PeekMessage(&m_msgCur, NULL, NULL, NULL, PM_NOREMOVE));中的::PeekMessage是什么用法?