How to enumerate all threads in a process?

[Lauriux1]

Maybe someone can show me how to enumerate all threads in a process?
I know that I should use CreateToolhelp32Snapshot, Process32First, Process32Next and I have made some attempts, but they was unsuccessful. So maybe someone could showe me how to do that correctly?

[Dungeon Keeper]

http://blogs.msdn.com/oldnewthing/ar...23/537856.aspx

[Lauriux1]

http://blogs.msdn.com/oldnewthing/ar...23/537856.aspx

Yes, I saw that before, but it doesn't help me much because I don't understand some parts of that code (it is not VB).

[Dungeon Keeper]

What exactly you don't understand there, ill try to translate it

[Lauriux1]

What exactly you don't understand there, ill try to translate it

I don't know, this code is missing some things, for example flags for CreateToolhelp32Snapshot and so on. Even if you'll translate this code, it will still be missing huge amount of code and other declarations. So I think that in this case, it is much more clever to write new code in VB from zero.

[Dungeon Keeper]

In any case you will need to declare those constants, structures and API functions to make it work in VB.

Here are some declarations:

Declare Function CreateToolhelp32Snapshot Lib "KERNEL32.dll" ( _ 
	 ByVal dwFlags As Long, _ 
	 ByVal th32ProcessID As Long) As Long 

Declare Function CloseHandle Lib "kernel32.dll" ( _ 
	 ByVal hObject As Long) As Long 

Const TH32CS_SNAPTHREAD As Long = &H4

Const INVALID_HANDLE_VALUE As Long = ((Handle) - 1) 'I think this indicates a function failure so you can use 0 for it.

You still need to find declarations for:
FIELD_OFFSET
THREADENTRY32

I have tested it and can guarantee that this code works, it shows process IDs and all thread IDs associated with that process ID, so it does what you need. You will only need to find the process EXE name if you want that too in your process/thread list.

I'm not sure about threads, but i doubt that threads have names - only IDs.

[Lauriux1]

I already have all needed declarations and constants. I just need help with code construction.

[Dungeon Keeper]

Then code would be:

Dim h As HANDLE 'or it maybe could be Long
h = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0)
IF h <> INVALID_HANDLE_VALUE THEN
Dim te As THREADENTRY32
te.dwSize = LenB(te)
if Thread32First(h, &te) THEN
    DO
        IF te.dwSize >= FIELD_OFFSET(THREADENTRY32, th32OwnerProcessID) + LenB(te.th32OwnerProcessID)) THEN
           MsgBox "Process " & te.th32OwnerProcessID & "Thread "  & te.th32ThreadID
        END IF
        te.dwSize = LenB(te)
    LOOP WHILE (Thread32Next(h, &te))
CloseHandle(h)