Rgui.exe 4.2.0 does not receive characters via the Windows API's PostMessage function

Dear Duncan,
I believe the problem is of a different nature.
I get TRUE 3 times running the code below:

procedure TfMain.btnPasteClick(Sender: TObject);
var
? i: integer;
? sTmp: string;
? hBN: HWND;
? j: bool;

begin
? hBN:= FindWindowA(nil,
??????????????????? 'R Console (64-bit)');

? sTmp:= 'sd';

? for i:= 1 to Length(sTmp) do begin
??? j:= PostMessage(hBN,
??????????????????? WM_CHAR,
??????????????????? Ord(sTmp[i]),
??????????????????? 0);

??? ShowMessage(BoolToStr(j,
????????????????????????? True));
? end;

? j:= PostMessage(hBN,
????????????? WM_KEYDOWN,
????????????? VK_RETURN, 0);

? ShowMessage(BoolToStr(j,
??????????????????????? True));
end;

That is, Rgui is receiving the message of the characters (via 
PostMessage), but it is blocking because it does not show them in the 
console.
The only thing Rgui blames is Carriage Return, as it adds an 
additional prompt with each run.

Best,
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
Jose Claudio Faria
UESC/DCET/Brasil
joseclaudio.faria at gmail.com
Telefones:
55(73)3680.5545 - UESC
55(73)99966.9100 - VIVO
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
If you have software to deal with statistics, you have arms,
if you have good software, you have arms and legs,
if you have software like R, you have arms, legs and wings...
the height of your flight depends only on you.

------ Mensagem original ------
De: "Duncan Murdoch" <murdoch.duncan at gmail.com>
Para: "jcfaria" <joseclaudio.faria at gmail.com>; r-devel at r-project.org
Enviado(s): 05/05/2022 13:17:53
Assunto: Re: [Rd] Rgui.exe 4.2.0 does not receive characters via the 
Windows API's PostMessage function

On 05/05/2022 11:17 a.m., jcfaria wrote:

Hello,

Rgui.exe 4.2.0 does not receive characters via the Windows API's
PostMessage function.

The Tinn-R project sends messages to Rgui.exe (SDI mode) via the 
Windows
API's PostMessage function.
A simplification of the code (in object Pascal) can be seen below.

procedure TfMain.btnPasteClick(Sender: TObject);
var
??? i: integer;
??? sTmp: WideString;
??? hBN: HWND;

begin
??? hBN:= FindWindowA(nil,
????????????????????? 'R Console (64-bit)');

??? sTmp:= 'sd';

??? for i:= 1 to Length(sTmp) do begin
????? PostMessage(hBN,
????????????????? WM_CHAR,
????????????????? Ord(sTmp[i]),
????????????????? 0);
??? end;

??? PostMessage(hBN,
??????????????? WM_KEYDOWN,
??????????????? VK_RETURN, 0);
end;

This code has always worked fine for all versions of Rgui.exe with the
exception of the last one released, ie 4.2.0.

We've been trying to get around the problem on the Object Pascal side,
but without success so far.

Does anyone connected to the compilation of Rqui.exe know what the
problem is?

It could be that the new build enforces Windows security more 
stringently.? More details are described in the answer to this 
question:? https://stackoverflow.com/a/40139498/2554330, but at a 
minimum you should be checking the return value from PostMessage.

Duncan Murdoch

Best,
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
Jose Claudio Faria
UESC/DCET/Brasil
joseclaudio.faria at gmail.com
Telefones:
55(73)3680.5545 - UESC
55(73)99966.9100 - VIVO
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
If you have software to deal with statistics, you have arms,
if you have good software, you have arms and legs,
if you have software like R, you have arms, legs and wings...
the height of your flight depends only on you.

????[[alternative HTML version deleted]]