Maybe there is something that I missed, I can't figure what is happening here.
I'm trying to load the same DLL in multiple instances of a TThread Object.
Here is my DLL code:
library MyCalcFor32;
uses
SysUtils,
Classes,
uRunner in 'uRunner.pas';
Exports EVal;
{$R *.res}
begin
end.
This is the uRunner.pas:
unit uRunner;
interface
uses SysUtils,
Classes;
function EVal(Valor: WideString): WideString; stdcall; export;
implementation
function EVal(Value: WideString): WideString; stdcall; export;
begin
Result := Value+' xxx';
end;
initialization
finalization
end.
This is the program to Load the DLL:
procedure TfrmMain.FormCreate(Sender: TObject);
var I: Integer;
begin
SetLength(Threads, 10);
for I:= 0 to 9 do
begin
Threads[I] := TWorker.Create(Self.Handle, I+1, Memo1.Text, ExtractFilePath(ParamStr(0)));
end;
end;
procedure TfrmMain.btnExecuteThreadsClick(Sender: TObject);
var I: Integer;
begin
ClearMemos([MT1, MT2, MT3, MT4, MT5, MT6, MT7, MT8, MT9, MT10]);
for I:= 0 to 0 do //to 9, for multiple
begin
if Threads[I].Suspended then
Threads[I].Resume
else
ShowMessage('Thread already in execution');
end;
end;
procedure TWorker.Execute;
var I: Integer;
J: Cardinal;
Ret: WideString;
A,B,C: Extended;
begin
CoInitialize(nil);
try
LoadDll;
while not Terminated do
begin
if not (Suspended or Terminated) then
begin
A := 310132041025;
B := 17592186044416;
C := 0;
for I:= 0 to 10 do
begin
if (Terminated) then begin
Break;
end;
for J:= 0 to 9999999 do
begin
if (Terminated) then begin
Break;
end;
A:= Sqrt(A);
if A <= 0 then begin
A:= 310132041025;
end
else begin
A:= Math.Power(A, 2);
end;
C:= C + (B-34 / 4);
B:= B / 2;
if B <= 0 then begin
B:= 17592186044416;
end;
end;
Ret := FEvalProcAddress(FEValValue);
NotifyMainForm(Format('Evaluate %s, resulted in %s', [IntToStr(I), Ret]));
end;
Suspend;
end;
Sleep(5000);
end;
finally
CoUninitialize;
end;
end;
procedure TWorker.LoadDll;
begin
//GlobalLock.Enter;
//try
FDLLHandle := LoadLibraryA(PChar(FPathApp + 'MyCalcFor32.dll'));
//finally
// GlobalLock.Leave;
//end;
if GetLastError <> 0 then
begin
NotifyTerminateThread;
end
else
begin
FEvalProcAddress := GetProcAddress(FDLLHandle, PChar('EVal'));
if GetLastError <> 0 then
begin
NotifyTerminateThread;
end;
end;
end;
When I have only 1 thread, it works just fine, but when I use multiple threads It raises the following exception:
System Error. Code: 87.
Incorrect Parameter
Note: The above code is just for reproduction;
I am aware of WideString + AnsiString problem.