How to check if a DLL is in use by any applications?

[djjd47130]

I am building an installer package which also installs some DLL's. I need to make this installer smart to where it recognizes when it has to copy/replace a DLL, it recognizes if any processes are using the DLL, returns details about each process, with the option to stop that process forcefully. So I need a function sort of like this:

procedure ListDLLProcesses(DLLFilename: String; List: TStrings);
begin
  //Find processes using the specified DLL as specified in 'DLLFilename'
  //Record each found process in 'List'
end;

Using Windows API's has never been a fun subject for me, so please keep it simple.

Thank you!


JD Solutions

 

[DjangMan]

What about Inno Setup as an option? It's free and industrial power.

There's also an add-on for Inno Setup to add the functionality that you're needing. It's 13 Euros or about $20.

http://rlbyte.com/product-details.php?id=7&show=desc

 

[Glenn9999]

Not exactly what you are asking for, but should give you a good shove in the right direction. This uses tlhelp32 so be sure you put that in the uses line.

procedure TForm1.Button1Click(Sender: TObject);
var
    ModLstHandle, ProcLstHandle: THandle;
    ModEntryProc: TModuleEntry32;
    ProcEntryProc: TProcessEntry32;
    CurrNode: TTreeNode;
begin
  TreeView1.Items.Clear;
  ProcLstHandle := CreateToolHelp32Snapshot(Th32CS_SNAPPROCESS, 0);
  if ProcLstHandle <> INVALID_HANDLE_VALUE then
    begin
      ProcEntryProc.dwSize := Sizeof(ProcEntryProc);
      if Process32First(proclstHandle, ProcEntryProc) then
        repeat
          CurrNode := TreeView1.Items.AddFirst(nil, ProcEntryProc.szExeFile);
          ModlstHandle := CreateToolhelp32Snapshot(TH32CS_SNAPMODULE,
                         ProcEntryProc.th32ProcessID);
          if ModLstHandle <> INVALID_HANDLE_VALUE then
            begin
              ModEntryProc.dwSize:=SizeOf(ModEntryProc);
              if Module32First(ModlstHandle, ModEntryProc) then
                begin
                  // Module32First always brings back
                  // main process module first, so skipping first call
                  While Module32Next(modLstHandle, ModEntryProc) do
                    TreeView1.Items.AddChild(CurrNode, ModEntryProc.szModule);
                  CloseHandle(ModlstHandle);
                end;
            end;
        until Not Process32Next(proclstHandle, ProcEntryProc);
      CloseHandle(procLstHandle);
    end;
end;

Specifically ModEntryProc.GlblcntUsage seems to return what you are looking for.

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