[Lazarus] send complex command to linux

[Andrew Haines]

On 12/18/10 13:49, ugaciaka wrote:
> Hi,
> 
> this is an example of what I do
> ===================================================
> 
> procedure TfrmMain.btnConvertClick(Sender: TObject);
> var
>   enumFile : TStringsEnumerator;
>   AProcess: TProcess;
>   AStringList: TStringList;
> begin
>   enumFile := clbFile.Items.GetEnumerator;
>   AProcess := TProcess.Create(nil);
>   AStringList := TStringList.Create;
> 
>   while enumFile.MoveNext do
>   begin
>     AProcess.CommandLine := 'flac -cd /home/ugaciaka/prova/prova.flac
> + | lame -h -b 320 - /home/ugaciaka/prova.mp3';
>     AProcess.Options := AProcess.Options + [poWaitOnExit, poUsePipes];
>     AProcess.Execute;
>     AStringList.LoadFromStream(AProcess.Output);
>     AStringList.SaveToFile('output.txt');
>   end;
>   AStringList.Free;
>   AProcess.Free;
> end;
> ====================================================================
> but not function, *but* if I write
> 
> AProcess.CommandLine := 'firefox gmail.google.com';
> 
> my process running correctly firefox.
> 
> In first case output.exe is similar to only ouput "lame".
> 
> Any resolution?

Hi,

I solved your issue using two TProcess instances:

===================
function Min(A, B: Integer): Integer;
begin
  if A > B then
    Result := B
  else
    Result := A;
end;

procedure TForm1.ConvertFile(AFile: String);
var
  Flac: TProcess;
  Lame: TProcess;
  NewFile: String;
  procedure PipeOutput;
  var
    Buffer: array[0..127] of byte;
    RCount: Integer;
  begin
    if Flac.Output.NumBytesAvailable > 0 then
    begin
      RCount := Flac.Output.Read(Buffer, Min(128,
Flac.Output.NumBytesAvailable));
      Lame.Input.Write(Buffer, RCount);
    end
    else
      Sleep(1);
  end;
begin
  NewFile := ExtractFileNameWithoutExt(AFile)+'.mp3';
  Flac := TProcess.Create(nil);
  Lame := TProcess.Create(nil);
  Flac.CommandLine := 'flac -cd '+ AFile;
  Lame.CommandLine := 'lame -h -b 320 - '+ NewFile;

  Flac.Options := [poUsePipes];
  Lame.Options := [poUsePipes];

  Flac.Execute;
  Lame.Execute;

  while Flac.Running or (Flac.Output.NumBytesAvailable > 0) do
    PipeOutput;

  Flac.Free;
  Lame.Free;
end;
=========================

Regards,

Andrew