Export (0) Print
Expand All

GetQueueStatus function

Retrieves the type of messages found in the calling thread's message queue.

Syntax


DWORD WINAPI GetQueueStatus(
  _In_  UINT flags
);

Parameters

flags [in]

Type: UINT

The types of messages for which to check. This parameter can be one or more of the following values.

ValueMeaning
QS_ALLEVENTS
(QS_INPUT | QS_POSTMESSAGE | QS_TIMER | QS_PAINT | QS_HOTKEY)

An input, WM_TIMER, WM_PAINT, WM_HOTKEY, or posted message is in the queue.

QS_ALLINPUT
(QS_INPUT | QS_POSTMESSAGE | QS_TIMER | QS_PAINT | QS_HOTKEY | QS_SENDMESSAGE)

Any message is in the queue.

QS_ALLPOSTMESSAGE
0x0100

A posted message (other than those listed here) is in the queue.

QS_HOTKEY
0x0080

A WM_HOTKEY message is in the queue.

QS_INPUT
(QS_MOUSE | QS_KEY | QS_RAWINPUT)

An input message is in the queue.

QS_KEY
0x0001

A WM_KEYUP, WM_KEYDOWN, WM_SYSKEYUP, or WM_SYSKEYDOWN message is in the queue.

QS_MOUSE
(QS_MOUSEMOVE | QS_MOUSEBUTTON)

A WM_MOUSEMOVE message or mouse-button message (WM_LBUTTONUP, WM_RBUTTONDOWN, and so on).

QS_MOUSEBUTTON
0x0004

A mouse-button message (WM_LBUTTONUP, WM_RBUTTONDOWN, and so on).

QS_MOUSEMOVE
0x0002

A WM_MOUSEMOVE message is in the queue.

QS_PAINT
0x0020

A WM_PAINT message is in the queue.

QS_POSTMESSAGE
0x0008

A posted message (other than those listed here) is in the queue.

QS_RAWINPUT
0x0400

A raw input message is in the queue. For more information, see Raw Input.

Windows 2000:  This flag is not supported.

QS_SENDMESSAGE
0x0040

A message sent by another thread or application is in the queue.

QS_TIMER
0x0010

A WM_TIMER message is in the queue.

 

Return value

Type:

Type: DWORD

The high-order word of the return value indicates the types of messages currently in the queue. The low-order word indicates the types of messages that have been added to the queue and that are still in the queue since the last call to the GetQueueStatus, GetMessage, or PeekMessage function.

Remarks

The presence of a QS_ flag in the return value does not guarantee that a subsequent call to the GetMessage or PeekMessage function will return a message. GetMessage and PeekMessage perform some internal filtering that may cause the message to be processed internally. For this reason, the return value from GetQueueStatus should be considered only a hint as to whether GetMessage or PeekMessage should be called.

The QS_ALLPOSTMESSAGE and QS_POSTMESSAGE flags differ in when they are cleared. QS_POSTMESSAGE is cleared when you call GetMessage or PeekMessage, whether or not you are filtering messages. QS_ALLPOSTMESSAGE is cleared when you call GetMessage or PeekMessage without filtering messages (wMsgFilterMin and wMsgFilterMax are 0). This can be useful when you call PeekMessage multiple times to get messages in different ranges.

Requirements

Minimum supported client

Windows 2000 Professional [desktop apps only]

Minimum supported server

Windows 2000 Server [desktop apps only]

Header

Winuser.h (include Windows.h)

Library

User32.lib

DLL

User32.dll

See also

Reference
GetInputState
GetMessage
PeekMessage
Conceptual
Messages and Message Queues

 

 

Community Additions

ADD
Show:
© 2014 Microsoft