MsgWaitForMultipleObjects issue

[manoj.m]

hai, i have one problem.
i just invoked a thread and i want to wait until the thread is over as well as no more keys are pressed. So i invoked MsgWaitForMultipleObjects with the following parameters.

HWND h = hwnd;
DWORD res = MsgWaitForMultipleObjects ( 1, &h, false, INFINITE, QS_INPUT );

According to MSDN it should return res = WAIT_OBJECT_0; But i am getting abs(difference) as 1 only. What i am missing in this,
Thanks in advance.

[wildfrog]

But i am getting abs(difference) as 1 only.You are getting what?

MsgWaitForMultipleObjects expects a handle to an event object, you're giving it a HWND.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/msgwaitformultipleobjects.asp

- petter

[manoj.m]

Sorry, i misstyped it, actually it is HANDLE only,
the difference b/w 'res' and WAIT_OBJECT_0 is '1' always, i think it must be the index of the handle.

[wildfrog]

If there are messages posted to the threads message queue then MsgWaitForMultipleObjects will return WAIT_OBJECT + n (where n is the number is event object you're wiating for).

So you probably need to handle those messages before you issue another MsgWaitForMultipleObject.

And, QS_INPUT wil react to both Mouse and Keyboard messages (>=XP Raw messages as well).

- petter

[KaramChand03]

Even I am having the same problem.

Basically, I created a thread using CreateThread(...) option. Now I want to come out of MsgWait... either when the thread is finished on there is an input from the keyboard.

After u get a return from MsgWait... I need to know which handle fired the exit from the function and process accordingly.

Since I am passing only one handle - WAIT_OBJECT_0 - return value should be 0, if it came out because thread got over, but it is returning some other value.

Do you have better idea about how to handle this?

[KaramChand03]

If there are messages posted to the threads message queue then MsgWaitForMultipleObjects will return WAIT_OBJECT + n (where n is the number is event object you're wiating for).

So you probably need to handle those messages before you issue another MsgWaitForMultipleObject.

And, QS_INPUT wil react to both Mouse and Keyboard messages (>=XP Raw messages as well).

- petter

So how do I only react to keyboard messages?

[wildfrog]

So how do I only react to keyboard messages?
Have you tried using QS_KEY instead of QS_INPUT?

- petter

[manoj.m]

Have you tried using QS_KEY instead of QS_INPUT?

- petter
Yes, i tried this also now, but the result is same.
i am pasting the code that i am using....

InvokeThread(); // invokes the thread
HANDLE h;
h = handle;//thread handle
DWORD res = MsgWaitForMultipleObjects ( 1, &h, false, INFINITE, QS_KEY );
if( ( WAIT_OBJECT_0-res ) == 0 )
Show_List();//This function uses a global structure that is filled by the thread.



--- the value that i am getting for res is always 1.

[wildfrog]

Have you seen the Waiting in a message loop (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/waiting_in_a_message_loop.asp) example?

the value that i am getting for res is always 1.What do you do when it return 1? The basic idea is that you should process the message (using a normal message loop), then return back to the MsgWaitForMultipleObjects call... just as in the example.

A call to Peek/GetMessage will 'reset' the message queue so that the next call to MsgWaitForMultipleObject won't react to 'old' messages.


- petter