native-code hangs after msg handler

[redcpu4ghz]

Hi:

I'm using VB Enterprise on W2K. I have a simple form app with a button handler. When I've compiled the code to p-code it works just fine, but when I compile to native code it hangs when it exits the message handler. When I go into Task Manager, it indicates my app is using 97-99% of the CPU.

I get the same results on XP.

Thanxs for your feedback,

redcpu

[MartinLiss]

Are you doing any "Advanced Optimizations"?

[redcpu4ghz]

No. I've tried "Fast Code" and "No Optimizations" on the Compile tab and both get the same results.

I suspect there's an infinite loop but it appears that infinite loop isn't in my code since the very last line of the msg handler is

MsgBox(.....)

which executes and then the hang occurs.

redcpu

[redcpu4ghz]

I also wonder if I have some stack corruption problem . I wish I could "debug" the native code .exe using a disassembler like VC++.

[Aaron Young]

Can you give us an idea of what the message handler is doing (a code snippet maybe)

[redcpu4ghz]

Private Sub Button_Click()

Dim buffer(8) As Byte
Dim retval As Long
Dim rc As Long

retval = SendCommand(2,6,0, buffer(), 6, 1, 8, 0)

If retval <> 1 Then
Msg.Text = Msg.Text & "Command failed ... exiting." & vbCrLf
End If

rc = MsgBox("GettingOuttaHere", vbOKOnly)

End Sub

The prototype for SendCommand is:

Declare Function SendCommand Lib "blah.dll" (ByVal firstparam As Long, ByVal secondparam As Long, ByVal thirdparam As Long, buffer() As Byte, ByVal length As Long, ByVal sixparam As Long, ByVal datalength As Long, ByVal eightparam As Long) As Integer

[redcpu4ghz]

Forgot to mention - the function SendCommand has the proper VB linkage, namely _stdcall (as opposed to cdecl linkage).

redcpu

[Aaron Young]

Have you identified that it's the code in the Button Click event that's causing the application to hang?

If not, try commenting out code in the event until the behavior stops.

[redcpu4ghz]

I've commented out the call to SendCommand and the hang doesn't occur. What's got me is why, when I compile to p-code, it all works?