Mutex: Difference between revisions

=={{header|Delphi}}==

{{libheader| Winapi.Windows}}

{{libheader| System.SysUtils}}

{{libheader| System.Classes}}

{{libheader| Vcl.Controls}}

{{libheader| Vcl.Forms}}

{{libheader| System.SyncObjs}}

{{libheader| Vcl.StdCtrls}}

<lang Delphi>

unit main;

interface

uses

Winapi.Windows, System.SysUtils, System.Classes, Vcl.Controls, Vcl.Forms,

System.SyncObjs, Vcl.StdCtrls;

type

TForm1 = class(TForm)

mmo1: TMemo;

btn1: TButton;

procedure FormCreate(Sender: TObject);

procedure FormDestroy(Sender: TObject);

procedure btn1Click(Sender: TObject);

private

{ Private declarations }

public

{ Public declarations }

end;

var

Form1: TForm1;

FMutex: TMutex;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);

begin

FMutex := TMutex.Create();

end;

procedure TForm1.FormDestroy(Sender: TObject);

begin

FMutex.Free;

end;

// http://edgarpavao.com/2017/08/07/multithreading-e-processamento-paralelo-no-delphi-ppl/

procedure TForm1.btn1Click(Sender: TObject);

begin

//Thread 1

TThread.CreateAnonymousThread(

procedure

begin

FMutex.Acquire;

try

TThread.Sleep(5000);

TThread.Synchronize(TThread.CurrentThread,

procedure

begin

mmo1.Lines.Add('Thread 1');

end);

finally

FMutex.Release;

end;

end).Start;

//Thread 2

TThread.CreateAnonymousThread(

procedure

begin

FMutex.Acquire;

try

TThread.Sleep(1000);

TThread.Synchronize(TThread.CurrentThread,

procedure

begin

mmo1.Lines.Add('Thread 2');

end);

finally

FMutex.Release;

end;

end).Start;

//Thread 3

TThread.CreateAnonymousThread(

procedure

begin

FMutex.Acquire;

try

TThread.Sleep(3000);

TThread.Synchronize(TThread.CurrentThread,

procedure

begin

mmo1.Lines.Add('Thread 3');

end);

finally

FMutex.Release;

end;

end).Start;

end;

end.</lang>

{{out}}

<pre>Thread 1

Thread 2

Thread 3</pre>