launching netsh to get the output - pascal

Question

I use this code:
proc := TProcess.Create(nil);
strList := TStringList.Create;
proc.Executable := 'netsh.exe';
proc.Parameters.Add('wlan');
proc.Parameters.Add('show');
proc.Parameters.Add('all');
proc.Options := proc.Options + [poWaitOnExit, poUsePipes];
proc.Execute;
strList.LoadFromStream(proc.Output);
proc.Free;
strList.Free;
The problem is netsh stay on screen (black command window) and do not stop.
If I remove poUsePipes, I can see clearly that netsh do the right job, output is correct.

Answer 1

It works with this code. I've understood the first method (in my question) generate to many bytes in the output so i had a deadlock. Mercy to https://wiki.freepascal.org/Executing_External_Programs (french version for me)
const
READ_BYTES = 2048;
var
Form1: TForm1;
proc: TProcess;
strList: TStringList;
ms: TMemoryStream;
n: LongInt;
br: LongInt;
i: longint;
implementation
{$R *.lfm}
{ TForm1 }
procedure TForm1.FormCreate(Sender: TObject);
begin
ms:=TMemoryStream.Create;
br:=0;
proc := TProcess.Create(nil);
strList := TStringList.Create;
proc.Executable := 'netsh.exe';
proc.Parameters.Add('wlan');
proc.Parameters.Add('show');
proc.Parameters.Add('all');
proc.Options := proc.Options + [poUsePipes];
proc.ShowWindow:=TShowWindowOptions.swoHIDE;
proc.Execute;
while proc.Running do
begin
ms.SetSize(br + READ_BYTES);
n:=proc.Output.Read((ms.Memory + br)^, READ_BYTES);
if n > 0
then begin
Inc(br, n);
end
else begin
//no data: wait 100ms
Sleep(100);
end;
end;
//read last part
repeat
ms.SetSize(br + READ_BYTES);
n:=proc.Output.Read((ms.Memory + br)^, READ_BYTES);
if n > 0
then begin
Inc(br, n);
end
until n <= 0;
ms.SetSize(br);
strList.LoadFromStream(ms);
proc.Free;
for i := 0 to strList.Count - 1 do
begin
memo.Append(CP437ToUTF8(strList.Strings[i]));
end;
strList.Free;
end;