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 win32 msgs: WM_TIMECHANGE

A message that is sent whenever there is a change in the system time.

A window receives this message through its WindowProc function.

    LRESULT CALLBACK WindowProc(
      HWND hwnd,       // handle to window
      UINT uMsg,       // message identifier
      WPARAM wParam,   // not used; must be zero
      LPARAM lParam    // not used; must be zero
    );

Parameters

• hwnd
A handle to window.
• uMsg
WM_TIMECHANGE identifier.
• wParam
Not used; must be zero.
• lParam
Not used; must be zero.

Return Value

An application should return zero if it processes this message.

Remarks

An application should not broadcast this message, because the system will broadcast this message when the application changes the system time.

Windows Me/98/95: An application should send this message to all top-level windows after changing the system time using the SendMessageTimeout function with HWND_TOPMOST. Do not send this message by calling SendMessage with HWND_BROADCAST.

Requirements

• Client
Requires Windows Vista, Windows XP, Windows 2000 Professional, Windows NT Workstation, Windows Me, Windows 98, or Windows 95.
• Server
Requires Windows Server 2008, Windows Server 2003, Windows 2000 Server, or Windows NT Server.
• Header
Declared in Winuser.h; include Windows.h.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time