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Threading !

What is the difference between "TerminateThread" and "ExitThread" APIs ?

I have created a new thread to process a lenghthy loop so VB doesn't hang and I can still get on with my other work during the loop.

I used the CreateThread API and it works as expected . What I CAN'T do is end the thread prematurely so I can exit the loop if it is far too long.

I have tried the 2 APIs above to kill the thread but it crashes the whole app ! (:

I have have already seen the example given on AllAPI.net Site and searched the net for other more info but I can't find anything that works to end a thread !!!

Does anybody have a working example with "TerminateThread" or "ExitThread" APIs to kill a thread ?

Thanks.

nffvrxqgrcfqvvc

Curious to know if you tested when your application was compiled and not from the IDE. Your application should crash if you compiled in native code. If you compile in p-code you have a better chance that createthread would work.

You can always get information from the remarks section of microsoft

TerminateThread
http://msdn.microsoft.com/library/en-us/dllproc/base/terminatethread.asp

ExitThread
http://msdn.microsoft.com/library/en-us/dllproc/base/exitthread.asp

RAFAAJ

ASKER

Thanks egl,

I am actually using VBA for this not VB so no real compiler.

I had already seen those links but I am afraid, they are not very clear\helpful...and as usual no real working code examples are given to illustrate the concepts (:

Any one has a concrete simple code that works ?

Regards.

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nffvrxqgrcfqvvc

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RAFAAJ

ASKER

OK, let me be a bit more specific.

Let's say that from within an Excel\VBA code, I want to seach the C drive for all files whose names include the letters "ab" and display the found files on a MsgBox.

Obviously this is a good scenario for wanting to run the loop in a seperate thread so the use can still work with XL while the lenghthy code is searching the C drive and all its Folders.

Using the CreateTread API all works fine for creating the new thread as well as running the lopp in its callback procedure. However if I wanted to abort the search , then I believe I would need to kill the Thread ...Right ?

To do so I am trying the TerminateThread as shown in the code below .Unfortuantely, I can't it to work. Worse still, the App crashes !!!

Code :

'In a module
Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Declare Function CreateThread Lib "kernel32" (lpThreadAttributes As Any, ByVal dwStackSize As Long, ByVal lpStartAddress As Long, lpParameter As Any, ByVal dwCreationFlags As Long, lpThreadID As Long) As Long
Declare Function TerminateThread Lib "kernel32" (ByVal hThread As Long, ByVal dwExitCode As Long) As Long
Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Public hThread As Long, hThreadID As Long

Public blnRepeatSearch As Boolean

Public Sub AsyncThread()

Dim strFiles As String
Dim i As Long
With Application.FileSearch
If blnRepeatSearch Then
.NewSearch
End If
.LookIn = "C:"
.SearchSubFolders = True
.Filename = "ab"
.MatchTextExactly = False
.FileType = msoFileTypeAllFiles
.Execute
For i = 1 To .FoundFiles.Count
strFiles = strFiles & vbCrLf & .FoundFiles(i)
Next i
End With
MsgBox strFiles
hThread = 0

End Sub

Sub StartThread()

If blnRepeatSearch = False Then
blnRepeatSearch = True
End If
hThread = CreateThread _
(ByVal 0&, ByVal 0&, AddressOf AsyncThread, ByVal 0&, ByVal 0&, hThreadID)
CloseHandle hThread

End Sub

Sub KillThread() ''''''''''''''''''NOT WORKING !!!!!

If hThread <> 0 Then TerminateThread hThread, 0

End Sub

Any one knows how to make the code above work ??? ( ie: Make the killTread procedure work )

Regards.

nffvrxqgrcfqvvc

You would want to use exitthread inside the AsyncThread callback, you must also make sure to exit any type of active loops before calling exit thread

RAFAAJ

ASKER

egl,

Any Idea how to apply that to the code ?

Thanks .