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copied!<p>Pipes are perfect for that job. You can implement a pipe reader thread at your service side and send corresponding string data through the pipe in ProcessFile method at client side.</p> <p>A quick, simple no error checking Pipe usage example:</p> <p>PipeServer</p> <pre><code>var Form1: TForm1; t: TReadpipe; h: THandle; msg: string; const BufSize=512; implementation {$R *.dfm} procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction); var chandle: THandle; begin t.Terminate; chandle := CreateFile('\\.\pipe\myNamedPipe', GENERIC_WRITE, 0, nil, OPEN_EXISTING, FILE_FLAG_WRITE_THROUGH, 0); CloseHandle(chandle); t.WaitFor; t.Free; CloseHandle(h); end; procedure TForm1.FormCreate(Sender: TObject); begin t := Treadpipe.Create(false); end; { TReadPipe } procedure TReadPipe.Execute; var buf: array [0 .. BufSize-1] of char; read: cardinal; begin while not Terminated do begin h := CreateNamedPipe('\\.\pipe\myNamedPipe', PIPE_ACCESS_DUPLEX, PIPE_TYPE_MESSAGE or PIPE_READMODE_MESSAGE or PIPE_WAIT, PIPE_UNLIMITED_INSTANCES, BufSize, BufSize, 0, nil); ConnectNamedPipe(h, nil); if Terminated then break; msg := ''; repeat FillChar(buf, BufSize, #0); ReadFile(h, buf[0], BufSize, read, nil); msg := msg + Copy(buf, 0, read); until GetLastError <> ERROR_MORE_DATA; if msg <> '' then Synchronize( procedure begin form1.Memo1.Lines.Add(msg) end); end; DisconnectNamedPipe(h); end; </code></pre> <p>PipeClient</p> <pre><code>var Form1: TForm1; i: Integer = 0; pipe: THandle; const BufSize = 512; implementation {$R *.dfm} procedure TForm1.Button1Click(Sender: TObject); var buf: array [0 .. BufSize - 1] of char; written: Cardinal; str: pchar; begin pipe := CreateFile('\\.\pipe\myNamedPipe', GENERIC_WRITE, 0, nil, OPEN_EXISTING, FILE_FLAG_WRITE_THROUGH, 0); if pipe = INVALID_HANDLE_VALUE then Halt; inc(i); str := pchar('someStr' + inttostr(i)); fillchar(buf, BufSize, #0); move(str[0], buf[0], Length(str) * Sizeof(char)); WriteFile(pipe, buf[0], Length(str) * Sizeof(char), written, nil); CloseHandle(pipe); end; </code></pre> <p>Also remember pipes works as FIFO.</p>

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