CloseWindow function (winuser.h)

Minimizes (but does not destroy) the specified window.

Syntax

BOOL CloseWindow(
  [in] HWND hWnd
);

[in] hWnd

Type: HWND

A handle to the window to be minimized.

Type: BOOL

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

To destroy a window, an application must use the DestroyWindow function.

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	winuser.h (include Windows.h)
Library	User32.lib
DLL	User32.dll
API set	ext-ms-win-ntuser-window-l1-1-4 (introduced in Windows 10, version 10.0.14393)