added multithreading examples

git-svn-id: trunk@9575 -

.gitattributes

@@ -994,11 +994,26 @@ examples/memotest.lpi svneol=native#text/plain
 examples/memotest.pp svneol=native#text/pascal
 examples/messagedialogs.lpi svneol=native#text/plain
 examples/messagedialogs.pp svneol=native#text/pascal
+examples/multithreading/criticalsectionexample1.lpi svneol=native#text/plain
+examples/multithreading/criticalsectionexample1.lpr svneol=native#text/plain
+examples/multithreading/criticalsectionunit1.lfm svneol=native#text/plain
+examples/multithreading/criticalsectionunit1.lrs svneol=native#text/plain
+examples/multithreading/criticalsectionunit1.pas svneol=native#text/plain
 examples/multithreading/mainunit.lfm svneol=native#text/plain
 examples/multithreading/mainunit.lrs svneol=native#text/plain
 examples/multithreading/mainunit.pas svneol=native#text/plain
 examples/multithreading/multithreadingexample1.lpi svneol=native#text/plain
 examples/multithreading/multithreadingexample1.lpr svneol=native#text/plain
+examples/multithreading/processmessagesunit1.lfm svneol=native#text/plain
+examples/multithreading/processmessagesunit1.lrs svneol=native#text/plain
+examples/multithreading/processmessagesunit1.pas svneol=native#text/plain
+examples/multithreading/singlethreadingexample1.lpi svneol=native#text/plain
+examples/multithreading/singlethreadingexample1.lpr svneol=native#text/plain
+examples/multithreading/waitforexample1.lpi svneol=native#text/plain
+examples/multithreading/waitforexample1.lpr svneol=native#text/plain
+examples/multithreading/waitforunit1.lfm svneol=native#text/plain
+examples/multithreading/waitforunit1.lrs svneol=native#text/plain
+examples/multithreading/waitforunit1.pas svneol=native#text/plain
 examples/notebk.lpi svneol=native#text/plain
 examples/notebk.pp svneol=native#text/pascal
 examples/notebku.pp svneol=native#text/pascal

examples/multithreading/criticalsectionexample1.lpi

@@ -0,0 +1,62 @@
+<?xml version="1.0"?>
+<CONFIG>
+  <ProjectOptions>
+    <PathDelim Value="/"/>
+    <Version Value="5"/>
+    <General>
+      <SessionStorage Value="InProjectDir"/>
+      <MainUnit Value="0"/>
+      <TargetFileExt Value=""/>
+    </General>
+    <PublishOptions>
+      <Version Value="2"/>
+      <IgnoreBinaries Value="False"/>
+      <IncludeFileFilter Value="*.(pas|pp|inc|lfm|lpr|lrs|lpi|lpk|sh|xml)"/>
+      <ExcludeFileFilter Value="*.(bak|ppu|ppw|o|so);*~;backup"/>
+    </PublishOptions>
+    <RunParams>
+      <local>
+        <FormatVersion Value="1"/>
+        <LaunchingApplication PathPlusParams="/usr/X11R6/bin/xterm -T 'Lazarus Run Output' -e $(LazarusDir)/tools/runwait.sh $(TargetCmdLine)"/>
+      </local>
+    </RunParams>
+    <RequiredPackages Count="1">
+      <Item1>
+        <PackageName Value="LCL"/>
+      </Item1>
+    </RequiredPackages>
+    <Units Count="2">
+      <Unit0>
+        <Filename Value="criticalsectionexample1.lpr"/>
+        <IsPartOfProject Value="True"/>
+        <UnitName Value="CriticalSectionExample1"/>
+      </Unit0>
+      <Unit1>
+        <Filename Value="criticalsectionunit1.pas"/>
+        <ComponentName Value="Form1"/>
+        <IsPartOfProject Value="True"/>
+        <ResourceFilename Value="criticalsectionunit1.lrs"/>
+        <UnitName Value="CriticalSectionUnit1"/>
+      </Unit1>
+    </Units>
+  </ProjectOptions>
+  <CompilerOptions>
+    <Version Value="5"/>
+    <SearchPaths>
+      <SrcPath Value="$(LazarusDir)/lcl/;$(LazarusDir)/lcl/interfaces/$(LCLWidgetType)/"/>
+    </SearchPaths>
+    <CodeGeneration>
+      <Generate Value="Faster"/>
+    </CodeGeneration>
+    <Linking>
+      <Options>
+        <Win32>
+          <GraphicApplication Value="True"/>
+        </Win32>
+      </Options>
+    </Linking>
+    <Other>
+      <CompilerPath Value="$(CompPath)"/>
+    </Other>
+  </CompilerOptions>
+</CONFIG>

examples/multithreading/criticalsectionexample1.lpr

@@ -0,0 +1,18 @@
+program CriticalSectionExample1;
+
+{$mode objfpc}{$H+}
+
+uses
+  {$IFDEF UNIX}
+  cthreads,
+  {$ENDIF}
+  Interfaces, // this includes the LCL widgetset
+  Forms
+  { add your units here }, CriticalSectionUnit1;
+
+begin
+  Application.Initialize;
+  Application.CreateForm(TForm1, Form1);
+  Application.Run;
+end.
+

examples/multithreading/criticalsectionunit1.lfm

@@ -0,0 +1,43 @@
+object Form1: TForm1
+  Caption = 'Form1'
+  ClientHeight = 169
+  ClientWidth = 312
+  PixelsPerInch = 75
+  HorzScrollBar.Page = 311
+  VertScrollBar.Page = 168
+  Left = 286
+  Height = 169
+  Top = 202
+  Width = 312
+  object Label1: TLabel
+    Caption = 'Label1'
+    Color = clNone
+    ParentColor = False
+    Left = 43
+    Height = 17
+    Top = 125
+    Width = 65
+  end
+  object CountWithCritSecButton: TButton
+    AutoSize = True
+    BorderSpacing.InnerBorder = 4
+    Caption = 'Count with critical section'
+    OnClick = CountWithCritSecButtonClick
+    TabOrder = 0
+    Left = 40
+    Height = 26
+    Top = 24
+    Width = 158
+  end
+  object CountWithoutCritSecButton: TButton
+    AutoSize = True
+    BorderSpacing.InnerBorder = 4
+    Caption = 'Count without critical section'
+    OnClick = CountWithoutCritSecButtonClick
+    TabOrder = 1
+    Left = 40
+    Height = 26
+    Top = 64
+    Width = 175
+  end
+end

examples/multithreading/criticalsectionunit1.lrs

@@ -0,0 +1,16 @@
+{ Dies ist eine automatisch erzeugte Lazarus-Ressourcendatei }
+
+LazarusResources.Add('TForm1','FORMDATA',[
+  'TPF0'#6'TForm1'#5'Form1'#7'Caption'#6#5'Form1'#12'ClientHeight'#3#169#0#11'C'
+  +'lientWidth'#3'8'#1#13'PixelsPerInch'#2'K'#18'HorzScrollBar.Page'#3'7'#1#18
+  +'VertScrollBar.Page'#3#168#0#4'Left'#3#30#1#6'Height'#3#169#0#3'Top'#3#202#0
+  +#5'Width'#3'8'#1#0#6'TLabel'#6'Label1'#7'Caption'#6#6'Label1'#5'Color'#7#6'c'
+  +'lNone'#11'ParentColor'#8#4'Left'#2'+'#6'Height'#2#17#3'Top'#2'}'#5'Width'#2
+  +'A'#0#0#7'TButton'#22'CountWithCritSecButton'#8'AutoSize'#9#25'BorderSpacing'
+  +'.InnerBorder'#2#4#7'Caption'#6#27'Count with critical section'#7'OnClick'#7
+  +#27'CountWithCritSecButtonClick'#8'TabOrder'#2#0#4'Left'#2'('#6'Height'#2#26
+  +#3'Top'#2#24#5'Width'#3#158#0#0#0#7'TButton'#25'CountWithoutCritSecButton'#8
+  +'AutoSize'#9#25'BorderSpacing.InnerBorder'#2#4#7'Caption'#6#30'Count without'
+  +' critical section'#7'OnClick'#7#30'CountWithoutCritSecButtonClick'#8'TabOrd'
+  +'er'#2#1#4'Left'#2'('#6'Height'#2#26#3'Top'#2'@'#5'Width'#3#175#0#0#0#0
+]);

examples/multithreading/criticalsectionunit1.pas

@@ -0,0 +1,147 @@
+{
+ ***************************************************************************
+ *                                                                         *
+ *   This source is free software; you can redistribute it and/or modify   *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This code is distributed in the hope that it will be useful, but      *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   A copy of the GNU General Public License is available on the World    *
+ *   Wide Web at <http://www.gnu.org/copyleft/gpl.html>. You can also      *
+ *   obtain it by writing to the Free Software Foundation,                 *
+ *   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.        *
+ *                                                                         *
+ ***************************************************************************
+
+  Abstract:
+    Demo to show how 5 threads increases a counter.
+    With and without critical sections.
+    
+    With critical sections you will always get 50000.
+    Without you will see different results on each run and depending on your
+    system.
+}
+unit CriticalSectionUnit1;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, Buttons,
+  StdCtrls, LCLProc, LCLType, LCLIntf;
+
+type
+
+  { TMyThread }
+
+  TMyThread = class(TThread)
+  public
+    procedure Execute; override;
+    property Finished: boolean read FFinished write FFinished;
+  end;
+
+  { TForm1 }
+
+  TForm1 = class(TForm)
+    CountWithoutCritSecButton: TButton;
+    CountWithCritSecButton: TButton;
+    Label1: TLabel;
+    procedure CountWithCritSecButtonClick(Sender: TObject);
+    procedure CountWithoutCritSecButtonClick(Sender: TObject);
+  private
+  public
+    CriticalSection: TCriticalSection;
+    Counter: integer;
+    UseCriticalSection: boolean;
+    procedure DoCounting;
+  end; 
+
+var
+  Form1: TForm1; 
+
+implementation
+
+{ TForm1 }
+
+procedure TForm1.CountWithCritSecButtonClick(Sender: TObject);
+begin
+  UseCriticalSection:=true;
+  DoCounting;
+end;
+
+procedure TForm1.CountWithoutCritSecButtonClick(Sender: TObject);
+begin
+  UseCriticalSection:=false;
+  DoCounting;
+end;
+
+procedure TForm1.DoCounting;
+var
+  i: Integer;
+  Threads: array[1..5] of TMyThread;
+  AllFinished: Boolean;
+begin
+  Counter:=0;
+  
+  // create the CriticalSection
+  InitializeCriticalSection(CriticalSection);
+
+  // start 5 threads
+  for i:=Low(Threads) to High(Threads) do
+    Threads[i]:=TMyThread.Create(false);
+  // wait till all threads finished
+  repeat
+    AllFinished:=true;
+    for i:=Low(Threads) to High(Threads) do
+      if not Threads[i].Finished then AllFinished:=false;
+  until AllFinished;
+  // free the threads
+  for i:=Low(Threads) to High(Threads) do
+    Threads[i].Free;
+
+  // free the CriticalSection
+  DeleteCriticalSection(CriticalSection);
+  
+  // show the Counter
+  Label1.Caption:='Counter='+IntToStr(Counter);
+end;
+
+{ TMyThread }
+
+procedure TMyThread.Execute;
+var
+  i: Integer;
+  CurCounter: LongInt;
+  j: Integer;
+begin
+  // increment the counter many times
+  // Because the other threads are doing the same, it will frequently happen,
+  // that 2 (or more) threads read the same number, increment it by one and
+  // write the result back, overwriting the result of the other threads.
+  for i:=1 to 100000 do begin
+    if Form1.UseCriticalSection then
+      EnterCriticalSection(Form1.CriticalSection);
+    try
+      CurCounter:=Form1.Counter;
+      for j:=1 to 1000 do ;
+      inc(CurCounter);
+      Form1.Counter:=CurCounter;
+    finally
+      if Form1.UseCriticalSection then
+        LeaveCriticalSection(Form1.CriticalSection);
+    end;
+  end;
+  Finished:=true;
+end;
+
+initialization
+  {$I criticalsectionunit1.lrs}
+
+end.
+

examples/multithreading/mainunit.pas

@@ -17,6 +17,12 @@
  *   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.        *
  *                                                                         *
  ***************************************************************************
+
+  Abstract:
+    Demo to show, how to start a thread and how synchronize with the main
+    thread.
+    Important: The cthread unint must be added to the uses section of the .lpr
+               file. See multithreadingexample1.lpr.
 }
 unit MainUnit;
 
@@ -60,18 +66,21 @@ procedure TForm1.FormCreate(Sender: TObject);
 var
   MyThread : TMyThread;
 begin
-   MyThread := TMyThread.Create(True); // This way it doesn't start automatically
+  MyThread := TMyThread.Create(True); // With the True parameter it doesn't start automatically
-   if Assigned(MyThread.FatalException) then
+  if Assigned(MyThread.FatalException) then
-     raise MyThread.FatalException;
+    raise MyThread.FatalException;
       
-   // Here the code initialises anything required before the threads starts executing
+  // Here the code initialises anything required before the threads starts executing
 
-   MyThread.Resume;
+  MyThread.Resume;
 end;
 
 { TMyThread }
 
 procedure TMyThread.ShowStatus;
+// this method is only called by Synchronize(@ShowStatus) and therefore
+// executed by the main thread
+// The main thread can access GUI elements, for example Form1.Caption.
 begin
   Form1.Caption := fStatusText;
 end;
@@ -80,13 +89,13 @@ procedure TMyThread.Execute;
 var
   newStatus : string;
 begin
-  fStatusText := 'Starting...';
+  fStatusText := 'TMyThread Starting...';
   Synchronize(@Showstatus);
-  fStatusText := 'Running...';
+  fStatusText := 'TMyThread Running...';
   while (not Terminated) and (true {any condition required}) do begin
 
     //here goes the code of the main thread loop
-    newStatus:='Time: '+FormatDateTime('YYYY-MM-DD HH:NN:SS',Now);
+    newStatus:='TMyThread Time: '+FormatDateTime('YYYY-MM-DD HH:NN:SS',Now);
     
     if NewStatus <> fStatusText then begin
       fStatusText := newStatus;

examples/multithreading/multithreadingexample1.lpi

@@ -6,12 +6,11 @@
     <General>
       <SessionStorage Value="InProjectDir"/>
       <MainUnit Value="0"/>
+      <IconPath Value="./"/>
       <TargetFileExt Value=""/>
     </General>
-    <LazDoc Paths=""/>
     <PublishOptions>
       <Version Value="2"/>
-      <IgnoreBinaries Value="False"/>
       <IncludeFileFilter Value="*.(pas|pp|inc|lfm|lpr|lrs|lpi|lpk|sh|xml)"/>
       <ExcludeFileFilter Value="*.(bak|ppu|ppw|o|so);*~;backup"/>
     </PublishOptions>

examples/multithreading/multithreadingexample1.lpr

@@ -3,12 +3,13 @@ program MultiThreadingExample1;
 {$mode objfpc}{$H+}
 
 uses
+  // for multi threading the cthreads unit must be used on unix systems:
+  // for example: Linux, MacOSX, FreeBSD, Solaris
   {$IFDEF UNIX}
   cthreads,
   {$ENDIF}
   Interfaces, // this includes the LCL widgetset
-  Forms
+  Forms, MainUnit;
-  { add your units here }, MainUnit;
 
 begin
   Application.Initialize;

examples/multithreading/processmessagesunit1.lfm

@@ -0,0 +1,34 @@
+object Form1: TForm1
+  Caption = 'Form1'
+  ClientHeight = 142
+  ClientWidth = 303
+  OnCreate = FormCreate
+  PixelsPerInch = 75
+  HorzScrollBar.Page = 302
+  VertScrollBar.Page = 141
+  Left = 286
+  Height = 142
+  Top = 202
+  Width = 303
+  object StartStopButton: TButton
+    Anchors = [akTop]
+    BorderSpacing.InnerBorder = 4
+    Caption = 'Start'
+    OnClick = StartStopButtonClick
+    TabOrder = 0
+    Left = 72
+    Height = 25
+    Top = 40
+    Width = 158
+  end
+  object ProgressBar1: TProgressBar
+    Anchors = [akTop, akLeft, akRight]
+    Max = 1000
+    Smooth = True
+    Step = 1
+    Left = 32
+    Height = 20
+    Top = 88
+    Width = 244
+  end
+end

examples/multithreading/processmessagesunit1.lrs

@@ -0,0 +1,14 @@
+{ Dies ist eine automatisch erzeugte Lazarus-Ressourcendatei }
+
+LazarusResources.Add('TForm1','FORMDATA',[
+  'TPF0'#6'TForm1'#5'Form1'#7'Caption'#6#5'Form1'#12'ClientHeight'#3#142#0#11'C'
+  +'lientWidth'#3'/'#1#8'OnCreate'#7#10'FormCreate'#13'PixelsPerInch'#2'K'#18'H'
+  +'orzScrollBar.Page'#3'.'#1#18'VertScrollBar.Page'#3#141#0#4'Left'#3#30#1#6'H'
+  +'eight'#3#142#0#3'Top'#3#202#0#5'Width'#3'/'#1#0#7'TButton'#15'StartStopButt'
+  +'on'#7'Anchors'#11#5'akTop'#0#25'BorderSpacing.InnerBorder'#2#4#7'Caption'#6
+  +#5'Start'#7'OnClick'#7#20'StartStopButtonClick'#8'TabOrder'#2#0#4'Left'#2'H'
+  +#6'Height'#2#25#3'Top'#2'('#5'Width'#3#158#0#0#0#12'TProgressBar'#12'Progres'
+  +'sBar1'#7'Anchors'#11#5'akTop'#6'akLeft'#7'akRight'#0#3'Max'#3#232#3#6'Smoot'
+  +'h'#9#4'Step'#2#1#4'Left'#2' '#6'Height'#2#20#3'Top'#2'X'#5'Width'#3#244#0#0
+  +#0#0
+]);

examples/multithreading/processmessagesunit1.pas

@@ -0,0 +1,138 @@
+{
+ ***************************************************************************
+ *                                                                         *
+ *   This source is free software; you can redistribute it and/or modify   *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This code is distributed in the hope that it will be useful, but      *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   A copy of the GNU General Public License is available on the World    *
+ *   Wide Web at <http://www.gnu.org/copyleft/gpl.html>. You can also      *
+ *   obtain it by writing to the Free Software Foundation,                 *
+ *   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.        *
+ *                                                                         *
+ ***************************************************************************
+
+  Abstract:
+    Demo to show, how to process a big file with the main thread.
+}
+unit ProcessMessagesUnit1;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, Buttons,
+  ComCtrls;
+
+type
+
+  { TForm1 }
+
+  TForm1 = class(TForm)
+    ProgressBar1: TProgressBar;
+    StartStopButton: TButton;
+    procedure FormCreate(Sender: TObject);
+    procedure StartStopButtonClick(Sender: TObject);
+  private
+    procedure Run;
+    procedure UpdateButton;
+  public
+    Running: boolean;
+    Aborting: boolean;
+    Filename: String;
+  end;
+
+var
+  Form1: TForm1; 
+
+implementation
+
+{ TForm1 }
+
+procedure TForm1.FormCreate(Sender: TObject);
+begin
+  Filename:='processmessagesunit1.pas';
+end;
+
+procedure TForm1.StartStopButtonClick(Sender: TObject);
+begin
+  if not Running then
+    Run
+  else
+    Aborting:=true;
+end;
+
+procedure TForm1.Run;
+var
+  fs: TFileStream;
+  Buffer: string;
+  Count: LongInt;
+  i: Integer;
+  Last: TDateTime;
+begin
+  if Running then exit;
+  Running:=true;
+  UpdateButton;
+  try
+    // open a file
+    fs:=TFileStream.Create(Filename,fmOpenRead);
+    try
+      SetLength(Buffer,10);
+      while true do begin
+
+        // process all user events, like clicking on the button
+        Application.ProcessMessages;
+        if Aborting or Application.Terminated then break;
+
+        // read some bytes
+        Count:=fs.Read(Buffer[1],length(Buffer));
+        if Count=0 then break;
+
+        // process ...
+        for i:=1 to Count do begin
+          Last:=Now;
+          repeat
+          until Now-Last>(double(1)/fs.Size)/10000;
+        end;
+
+        // show progress
+        ProgressBar1.Position:=ProgressBar1.Min
+               +((ProgressBar1.Max-ProgressBar1.Min+1)*fs.Position) div fs.Size;
+      end;
+    finally
+      fs.Free;
+    end;
+  except
+    on E: Exception do begin
+      MessageDlg('Error',E.Message,mtError,[mbCancel],0);
+    end;
+  end;
+  Aborting:=false;
+  Running:=false;
+  UpdateButton;
+end;
+
+procedure TForm1.UpdateButton;
+begin
+  if Running then begin
+    if Aborting then
+      StartStopButton.Caption:='Aborting ...'
+    else
+      StartStopButton.Caption:='Running ...';
+  end else begin
+    StartStopButton.Caption:='Start';
+  end;
+end;
+
+initialization
+  {$I processmessagesunit1.lrs}
+
+end.
+

examples/multithreading/singlethreadingexample1.lpi

@@ -0,0 +1,63 @@
+<?xml version="1.0"?>
+<CONFIG>
+  <ProjectOptions>
+    <PathDelim Value="/"/>
+    <Version Value="5"/>
+    <General>
+      <SessionStorage Value="InProjectDir"/>
+      <MainUnit Value="0"/>
+      <IconPath Value="./"/>
+      <TargetFileExt Value=""/>
+    </General>
+    <PublishOptions>
+      <Version Value="2"/>
+      <IgnoreBinaries Value="False"/>
+      <IncludeFileFilter Value="*.(pas|pp|inc|lfm|lpr|lrs|lpi|lpk|sh|xml)"/>
+      <ExcludeFileFilter Value="*.(bak|ppu|ppw|o|so);*~;backup"/>
+    </PublishOptions>
+    <RunParams>
+      <local>
+        <FormatVersion Value="1"/>
+        <LaunchingApplication PathPlusParams="/usr/X11R6/bin/xterm -T 'Lazarus Run Output' -e $(LazarusDir)/tools/runwait.sh $(TargetCmdLine)"/>
+      </local>
+    </RunParams>
+    <RequiredPackages Count="1">
+      <Item1>
+        <PackageName Value="LCL"/>
+      </Item1>
+    </RequiredPackages>
+    <Units Count="2">
+      <Unit0>
+        <Filename Value="singlethreadingexample1.lpr"/>
+        <IsPartOfProject Value="True"/>
+        <UnitName Value="SingleThreadingExample1"/>
+      </Unit0>
+      <Unit1>
+        <Filename Value="processmessagesunit1.pas"/>
+        <ComponentName Value="Form1"/>
+        <IsPartOfProject Value="True"/>
+        <ResourceFilename Value="processmessagesunit1.lrs"/>
+        <UnitName Value="ProcessMessagesUnit1"/>
+      </Unit1>
+    </Units>
+  </ProjectOptions>
+  <CompilerOptions>
+    <Version Value="5"/>
+    <SearchPaths>
+      <SrcPath Value="$(LazarusDir)/lcl/;$(LazarusDir)/lcl/interfaces/$(LCLWidgetType)/"/>
+    </SearchPaths>
+    <CodeGeneration>
+      <Generate Value="Faster"/>
+    </CodeGeneration>
+    <Linking>
+      <Options>
+        <Win32>
+          <GraphicApplication Value="True"/>
+        </Win32>
+      </Options>
+    </Linking>
+    <Other>
+      <CompilerPath Value="$(CompPath)"/>
+    </Other>
+  </CompilerOptions>
+</CONFIG>

examples/multithreading/singlethreadingexample1.lpr

@@ -0,0 +1,18 @@
+program SingleThreadingExample1;
+
+{$mode objfpc}{$H+}
+
+uses
+  {$IFDEF UNIX}{$IFDEF UseCThreads}
+  cthreads,
+  {$ENDIF}{$ENDIF}
+  Interfaces, // this includes the LCL widgetset
+  Forms
+  { add your units here }, ProcessMessagesUnit1;
+
+begin
+  Application.Initialize;
+  Application.CreateForm(TForm1, Form1);
+  Application.Run;
+end.
+

examples/multithreading/waitforexample1.lpi

@@ -0,0 +1,244 @@
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+</CONFIG>

examples/multithreading/waitforexample1.lpr

@@ -0,0 +1,18 @@
+program WaitForExample1;
+
+{$mode objfpc}{$H+}
+
+uses
+  {$IFDEF UNIX}
+  cthreads,
+  {$ENDIF}
+  Interfaces, // this includes the LCL widgetset
+  Forms
+  { add your units here }, WaitForUnit1;
+
+begin
+  Application.Initialize;
+  Application.CreateForm(TForm1, Form1);
+  Application.Run;
+end.
+

examples/multithreading/waitforunit1.lfm

@@ -0,0 +1,32 @@
+object Form1: TForm1
+  ActiveControl = Button1
+  Caption = 'Form1'
+  ClientHeight = 359
+  ClientWidth = 394
+  OnCreate = FormCreate
+  OnDestroy = FormDestroy
+  PixelsPerInch = 75
+  HorzScrollBar.Page = 393
+  VertScrollBar.Page = 358
+  Left = 286
+  Height = 359
+  Top = 202
+  Width = 394
+  object Button1: TButton
+    BorderSpacing.InnerBorder = 4
+    Caption = 'Start'
+    OnClick = Button1Click
+    TabOrder = 0
+    Left = 32
+    Height = 25
+    Top = 16
+    Width = 75
+  end
+  object Memo1: TMemo
+    Align = alBottom
+    TabOrder = 1
+    Height = 303
+    Top = 56
+    Width = 394
+  end
+end

examples/multithreading/waitforunit1.lrs

@@ -0,0 +1,13 @@
+{ Dies ist eine automatisch erzeugte Lazarus-Ressourcendatei }
+
+LazarusResources.Add('TForm1','FORMDATA',[
+  'TPF0'#6'TForm1'#5'Form1'#13'ActiveControl'#7#7'Button1'#7'Caption'#6#5'Form1'
+  +#12'ClientHeight'#3'g'#1#11'ClientWidth'#3#138#1#8'OnCreate'#7#10'FormCreate'
+  +#9'OnDestroy'#7#11'FormDestroy'#13'PixelsPerInch'#2'K'#18'HorzScrollBar.Page'
+  +#3#137#1#18'VertScrollBar.Page'#3'f'#1#4'Left'#3#30#1#6'Height'#3'g'#1#3'Top'
+  +#3#202#0#5'Width'#3#138#1#0#7'TButton'#7'Button1'#25'BorderSpacing.InnerBord'
+  +'er'#2#4#7'Caption'#6#5'Start'#7'OnClick'#7#12'Button1Click'#8'TabOrder'#2#0
+  +#4'Left'#2' '#6'Height'#2#25#3'Top'#2#16#5'Width'#2'K'#0#0#5'TMemo'#5'Memo1'
+  +#5'Align'#7#8'alBottom'#8'TabOrder'#2#1#6'Height'#3'/'#1#3'Top'#2'8'#5'Width'
+  +#3#138#1#0#0#0
+]);

examples/multithreading/waitforunit1.pas

@@ -0,0 +1,162 @@
+{
+ ***************************************************************************
+ *                                                                         *
+ *   This source is free software; you can redistribute it and/or modify   *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This code is distributed in the hope that it will be useful, but      *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
+ *   General Public License for more details.                              *
+ *                                                                         *
+ *   A copy of the GNU General Public License is available on the World    *
+ *   Wide Web at <http://www.gnu.org/copyleft/gpl.html>. You can also      *
+ *   obtain it by writing to the Free Software Foundation,                 *
+ *   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.        *
+ *                                                                         *
+ ***************************************************************************
+
+  Abstract:
+    Demo to show, how a Thread waits for another.
+}
+unit WaitForUnit1;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, Buttons,
+  StdCtrls, LCLProc;
+
+type
+
+  { TBaseThread }
+
+  TBaseThread = class(TThread)
+  public
+    procedure Log(const Msg: string; AppendLineEnd: boolean = true);
+  end;
+
+  { TThreadA }
+
+  TThreadA = class(TBaseThread)
+  public
+    WaitForB: PRtlEvent;
+    procedure Execute; override;
+  end;
+
+  { TThreadB }
+
+  TThreadB = class(TBaseThread)
+  private
+    FCounter: integer;
+  public
+    procedure Execute; override;
+    property Counter: integer read FCounter write FCounter;
+  end;
+
+  { TForm1 }
+
+  TForm1 = class(TForm)
+    Button1: TButton;
+    Memo1: TMemo;
+    procedure Button1Click(Sender: TObject);
+    procedure FormCreate(Sender: TObject);
+    procedure FormDestroy(Sender: TObject);
+  private
+    ACriticalSection: TRTLCriticalSection;
+    MsgText: string;
+    procedure AddMessage;
+  public
+    ThreadA: TThreadA;
+    ThreadB: TThreadB;
+  end;
+
+var
+  Form1: TForm1; 
+
+implementation
+
+{ TForm1 }
+
+procedure TForm1.Button1Click(Sender: TObject);
+begin
+  if ThreadA=nil then
+    ThreadA:=TThreadA.Create(false);
+end;
+
+procedure TForm1.FormCreate(Sender: TObject);
+begin
+  InitCriticalSection(ACriticalSection);
+end;
+
+procedure TForm1.FormDestroy(Sender: TObject);
+begin
+  DoneCriticalsection(ACriticalSection);
+end;
+
+procedure TForm1.AddMessage;
+begin
+  Memo1.Lines.Text:=MsgText;
+end;
+
+{ TThreadA }
+
+procedure TThreadA.Execute;
+begin
+  Form1.ThreadB:=TThreadB.Create(false);
+  // create event
+  WaitForB:=RTLEventCreate;
+  while not Application.Terminated do begin
+    Log('A: wait for B ...');
+    // wait infinitely (until B wakes A)
+    RtlEventWaitFor(WaitForB);
+    Log('A: ThreadB.Counter='+IntToStr(Form1.ThreadB.Counter));
+  end;
+end;
+
+{ TThreadB }
+
+procedure TThreadB.Execute;
+var
+  i: Integer;
+begin
+  Counter:=0;
+  while not Application.Terminated do begin
+    Log('B: Working ...');
+    for i:=1 to 5 do begin
+      Sleep(300);
+      Log('.....  ',false);
+    end;
+    Log('');
+    inc(Counter);
+    Log('B: Wake A');
+    // wake A
+    RtlEventSetEvent(Form1.ThreadA.WaitForB);
+  end;
+end;
+
+{ TBaseThread }
+
+procedure TBaseThread.Log(const Msg: string; AppendLineEnd: boolean);
+var
+  s: String;
+begin
+  EnterCriticalsection(Form1.ACriticalSection);
+  s:=Msg;
+  if AppendLineEnd then
+    s:=s+LineEnding;
+  dbgout(s);
+  Form1.MsgText:=Form1.MsgText+s;
+  Synchronize(@Form1.AddMessage);
+  LeaveCriticalsection(Form1.ACriticalSection);
+end;
+
+initialization
+  {$I waitforunit1.lrs}
+
+end.
+