How can I get a list with all the threads created by my application

Question

Hi,

I want to get a list with all the threads (except the main, GUI thread) from within my application in order to do some action(s) with them. (set priority, kill, pause etc.) How to do that?

Answer 1

You can also have a look at http://blog.delphi-jedi.net/2008/03/19/how-to-get-the-threads-of-a-process/

Answer 2

You can access this information using WMI.
The WIN32_Process can give you all information about process executing on Machine. For each process you can give ThreadsCount, Handle,...

Another class, WIN32_Thread can give you detailled information about all Threads running on Machine. This class hace a property called ProcessId for search especific threads for 1 process (class WIN32_Process).

For test it you can execute this on CommandLine window:

// all processes    
WMIC PROCESS   
// information about Delphi32    
WMIC PROCESS WHERE Name="delphi32.exe"   
// some information about Delphi32    
WMIC PROCESS WHERE Name="delphi32.exe" GET Name,descrption,threadcount,Handle
(NOTE: The handle for delphi32.exe in my machine is **3680**)

Similar you can do with WIN32_Thread using the Handle of process.

Excuse.me for my bad english.

Regards.

Answer 3

You can use my TProcessInfo class:

var
  CurrentProcess : TProcessItem;
  Thread : TThreadItem;
begin
  ProcessInfo1.UpdateList;
  CurrentProcess := ProcessInfo1.RunningProcesses.FindByID(GetCurrentProcessId);
  for Thread in CurrentProcess.Threads do
    Memo1.Lines.Add(Thread.ToString);
end;

Answer 4

Another option is use the CreateToolhelp32Snapshot,Thread32First and Thread32Next functions.

See this very simple example (Tested in Delphi 7 and Windows 7).

program ListthreadsofProcess;

{$APPTYPE CONSOLE}

uses
  PsAPI,
  TlHelp32,
  Windows,
  SysUtils;

function GetTthreadsList(PID:Cardinal): Boolean;
  var
    SnapProcHandle: THandle;
    NextProc      : Boolean;
    TThreadEntry  : TThreadEntry32;
  begin
    SnapProcHandle := CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0); //Takes a snapshot of the all threads
    Result := (SnapProcHandle <> INVALID_HANDLE_VALUE);
    if Result then
      try
        TThreadEntry.dwSize := SizeOf(TThreadEntry);
        NextProc := Thread32First(SnapProcHandle, TThreadEntry);//get the first Thread
        while NextProc do
        begin

          if TThreadEntry.th32OwnerProcessID = PID then //Check the owner Pid against the PID requested
          begin
              Writeln('Thread ID      '+inttohex(TThreadEntry.th32ThreadID,8));
              Writeln('base priority  '+inttostr(TThreadEntry.tpBasePri));
              Writeln('delta priority '+inttostr(TThreadEntry.tpBasePri));
              Writeln('');
          end;

          NextProc := Thread32Next(SnapProcHandle, TThreadEntry);//get the Next Thread
        end;
      finally
        CloseHandle(SnapProcHandle);//Close the Handle
      end;
  end;

begin
  { TODO -oUser -cConsole Main : Insert code here }
  GettthreadsList(GetCurrentProcessId); //get the PID of the current application
  //GettthreadsList(5928);
  Readln;
end.

Answer 5

If they are your threads, then I would create an application global Thread Manager to register themselves with upon creation. Then you can properly monitor, pause and shutdown threads gracefully using your Thread Manager.