[fpc-devel] OO rewrite - technical questions

[Michael Schnell]

  On 07/24/2010 05:12 PM, Hans-Peter Diettrich wrote:
>
> In the meantime I found one possible use for threadvars: when some 
> subroutine can be called from different threads, it may want to 
> retrieve the thread context, e.g. the thread object itself. Right?
Yep. But of course you can do multiple threads that completely execute 
the same code (e.g. a Web Server that handles multiple externals 
requests at the same time.

-Michael

Here a simple test program with threadvars;

unit Unit61;

interface

uses
   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, 
Forms,
   Dialogs, StdCtrls;

type
   TForm61 = class(TForm)
     Button1: TButton;
     Button2: TButton;
     procedure FormCreate(Sender: TObject);
     procedure Button1Click(Sender: TObject);
   private
     { Private declarations }
   public
     { Public declarations }
   end;

   TMyThread = class(TThread)
     procedure execute; override;
   end;

var
   Form61: TForm61;
   test: Integer;
   teststr: String;

   MyThread1, MyThread2 : TMythread;

threadvar threadtest: Integer;



implementation

{$R *.dfm}

function dotest: String;
begin
   inc(test);
   inc(threadtest);
   Result := IntToStr(test) + '/' + IntToStr(threadtest);
end;



procedure TForm61.Button1Click(Sender: TObject);
var s: String;
begin
   s := dotest;
   teststr := teststr + ' ' + s;
   caption := teststr;
end;

procedure TForm61.FormCreate(Sender: TObject);
begin
   test := 10;
   threadtest := 20;
   MyThread1 := TMythread.Create(false);
   MyThread2 := TMythread.Create(false);
end;

{ TMyThread }

procedure TMyThread.execute;
var s: String;
begin
   s:= dotest;
   teststr := teststr + ' .. ' + s;
   while (true) do
     sleep(10000);
end;

end.