R devel - May 2022 - Rgui.exe 4.2.0 does not receive characters via the Windows API's PostMessage function

Dear Jose,

On 5/15/22 01:31, jcfaria wrote:
> Dear Tomas,
>
> I am very grateful for your attention!
>
> I've been reading some things about the GraphApp 
> toolkit(http://enchantia.com/software/graphapp/) that is being used in 
> the development of new versions of Rgui.
>
> Really, if it's a matter of choice, the problems I reported cannot be 
> considered a "bug". It's up to us - GUI and IDE application
developers
> - to adapt to the new features.
>
> I'm studying how to get around the problem, but I still haven't
found
> a simple way.
>
> The solution you proposed (code below) ran fine here in all versions 
> of Rgui I have installed, but it's working only for very simple 
> strings, like the one I tested. When testing the needs close to the 
> real I found some problems.
>
> For example, when sending the string below:
> - char *s = "(s <- c('?', 'b', 'c',
'?'))";
>
> Rgui receives:
> > 9s ,- c9'', 'b', 'c', ''00
> Error: unexpected symbol in "9s"
> >
>
>
> #include <windows.h>
> #include <stdio.h>
> #include <string.h>
>
> int main(int argc, char **argv) {
> ?? HWND hw;
> ?? int i, res;
>
> ?? printf("Getting Rgui window...\n");
> ?? hw = FindWindow(NULL, "R Console (64-bit)");
>
> ?? printf("Got window: %x\n", hw);
> ?? if (hw == NULL) {
> ???? printf("Could not get Rgui window: %x\n", GetLastError());
> ???? return 2;
> ?? }
>
> ?? //Samples to send:
> // char *s = "sd";
> ?? char *s = "(s <- c('?', 'b', 'c',
'?'))";
>
> ?? for(i = 0; i < strlen(s); i++) {
> ???? res = PostMessage(hw, WM_KEYDOWN, VkKeyScan(s[i]), 0);
> ???? printf("Sending char %c: %d.\n", s[i], res);
> ?? }
>
> ?? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
> ?? printf("Sending return: %d\n.", res);
> ?? return 0;
> }
>
> The idea of Tinn-R communicating with Rgui.exe is to take advantage of 
> the great stability of Rgui. Since communication with Rterm is done 
> via pipe.
>
> I believe that developing a new interface using the resources of the 
> R.dll library, as proposed, is outside the simple purposes of the 
> Tinn-R project.
>
> Any help in this regard is welcome.
If embedding R seems too involved, and the hack above doesn't work well 
enough, perhaps you could use SendInput() (also mentioned in the blog 
post [1] below as a more correct way to inject input as WM_KEYDOWN).? 
This is an example:

---

#include <windows.h>
#include <stdio.h>

int main(int argc, char **argv) {
 ? HWND hw, ow;
 ? int i, res;

 ? hw = FindWindow(NULL, "R Console (64-bit)");
 ? if (hw == NULL) {
 ??? printf("Could not get Rgui window: %x\n", GetLastError());
 ??? return 2;
 ? }

 ? ow = GetForegroundWindow();
 ? if (ow == NULL)
 ??? printf("Foreground window is NULL\n");

 ? if (!SetForegroundWindow(hw))
 ??? printf("Could not set Rgui as foreground window\n");

 ? char *sd = "sd";
 ? for(i = 0; i < strlen(sd); i++) {
 ??? INPUT input;

 ??? ZeroMemory(&input, sizeof(INPUT));
 ??? input.type = INPUT_KEYBOARD;
 ??? input.ki.dwFlags = KEYEVENTF_UNICODE;
 ??? input.ki.wScan = (unsigned) sd[i];
 ??? res = SendInput(1, &input, sizeof(INPUT));

 ??? printf("Sending char %c (%x): %d.\n", sd[i], sd[i], res);
 ? }

 ? {
 ??? INPUT input[2];

 ??? ZeroMemory(input, 2*sizeof(INPUT));
 ??? input[0].type = input[1].type = INPUT_KEYBOARD;
 ??? input[1].ki.dwFlags = KEYEVENTF_KEYUP;
 ??? input[0].ki.wVk = input[1].ki.wVk = VK_RETURN;
 ??? res = SendInput(2, input, sizeof(INPUT));
 ??? printf("Sending return: %d.\n", res);
 ? }

 ? if (!SetForegroundWindow(ow))
 ??? printf("Could not set the original window as foreground");

 ? return 0;
}

---

This example works for me with R 4.1.3 and with R-devel 82368. It 
doesn't work with R 4.2.0 (see a related thread about Dasher on this list).

Best
Tomas
>
> 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: "Tomas Kalibera" <tomas.kalibera at gmail.com>
> Para: "jcfaria" <joseclaudio.faria at gmail.com>;
"Duncan Murdoch"
> <murdoch.duncan at gmail.com>; r-devel at r-project.org
> Enviado(s): 11/05/2022 13:32:23
> Assunto: Re: [Rd] Rgui.exe 4.2.0 does not receive characters via the 
> Windows API's PostMessage function
>
>>
>> On 5/11/22 15:39, Tomas Kalibera wrote:
>>>
>>> On 5/11/22 08:15, Tomas Kalibera wrote:
>>>>
>>>> On 5/11/22 03:02, jcfaria wrote:
>>>>> Dear Tomas,
>>>>> I've tried, but I don't have the necessary C/C++
programming
>>>>> skills to fulfill your request.
>>>>>
>>>>> Maybe someone can help us by transcribing the little code
in
>>>>> object Pascal that I sent to C/C++.
>>>>>
>>>>> If a small executable, made in Object Pascal, can help in
your
>>>>> debug, I can provide.
>>>>
>>>> Dear Jose,
>>>>
>>>> no problem, I can try out with the Pascal code.
>>>> Is there a free compiler I can use to build and run it?
>>>
>>> Actually I can reproduce it in a C program doing the same thing.
>>>
>>> The primary cause is that Rgui is using GraphApp Unicode windows on
>>> systems running in a multi-byte locale, which affects most systems 
>>> since R 4.2 because of the switch to UTF-8. While Unicode windows 
>>> have been used even in older versions of R, it was only on systems 
>>> then running in a multi-byte locale, and apparently this hasn't
been
>>> reported.
>>>
>>> When I modify R-devel to use non-Unicode GraphApp windows, the 
>>> message sending works again. I will have a closer look, thanks for 
>>> the report.
>>
>> I had a closer look and this doesn't really seem to be a bug in R
to
>> me. For Unicode Windows, GraphApp uses WM_IME_COMPOSITION messages to 
>> read the keys instead of WM_CHAR, which it uses for non-Unicode 
>> windows. This is internal functionality of Rgui and a legitimate 
>> choice. Rgui cannot simply handle both messages in Unicode windows, 
>> because the characters would be doubled (if you see an easy, elegant 
>> change to Rgui that would mimic the previous behavior, let me know). 
>> This is certainly not a documented interface for Rgui, so I am afraid 
>> you would have to change something in your application.
>>
>> I read that using PostMessage to simulate keyboard input is 
>> considered wrong, see [1], and then one should instead use SendInput 
>> (which then requires bringing the window to the foreground), if at 
>> all simulating keyboard input. Maybe one could create a better 
>> working solution that way, or using some automation library.
>>
>> As a quick hack, I found that [2] happens to be working on my system, 
>> but again relying on the current implementation of Rgui (simply you 
>> send WM_KEYDOWN also for the characters other than the 
>> newline/return). It seems to be working also with R 4.1 for me.
>>
>> The usual way for GUIs/front-ends is to "embed" R, to link it
as a
>> DLL. Rgui itself does it and also external applications such as 
>> RStudio. Typically you would want to have a thin layer application 
>> embedding R and make your GUI communicate with that, but switching to 
>> that from sending the messages would require some work.
>>
>> Best
>> Tomas
>>
>> [1] https://devblogs.microsoft.com/oldnewthing/20050530-11/?p=35513
>>
>> [2]
>> #include <windows.h>
>> #include <stdio.h>
>> #include <string.h>
>>
>> int main(int argc, char **argv) {
>> ? HWND hw;
>> ? int i, res;
>>
>> ? printf("Getting Rgui window...\n");
>> ? hw = FindWindow(NULL, "R Console (64-bit)");
>>
>> ? printf("Got window: %x\n", hw);
>> ? if (hw == NULL) {
>> ??? printf("Could not get Rgui window: %x\n",
GetLastError());
>> ??? return 2;
>> ? }
>>
>> ? char *sd = "sd";
>> ? for(i = 0; i < strlen(sd); i++) {
>> ??? res = PostMessage(hw, WM_KEYDOWN, VkKeyScan(sd[i]), 0);
>> ??? printf("Sending char %c: %d.\n", sd[i], res);
>> ? }
>>
>> ? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
>> ? printf("Sending return: %d\n.", res);
>> ? return 0;
>> }
>>
>>
>>>
>>> For reference, to reproduce I ran
>>>
>>> Rgui --sdi
>>>
>>> and used this C example:
>>>
>>> #include <windows.h>
>>> #include <stdio.h>
>>> #include <string.h>
>>>
>>> int main(int argc, char **argv) {
>>> ? HWND hw;
>>> ? int i, res;
>>>
>>> ? printf("Getting Rgui window...\n");
>>> ? hw = FindWindow(NULL, "R Console (64-bit)");
>>>
>>> ? printf("Got window: %x\n", hw);
>>> ? if (hw == NULL) {
>>> ??? printf("Could not get Rgui window: %x\n",
GetLastError());
>>> ??? return 2;
>>> ? }
>>>
>>> ? char *sd = "sd";
>>> ? for(i = 0; i < strlen(sd); i++) {
>>> ??? res = PostMessage(hw, WM_CHAR, (unsigned int) sd[i], 0);
>>> ??? printf("Sending char %c: %d.\n", sd[i], res);
>>> ? }
>>>
>>> ? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
>>> ? printf("Sending return: %d\n.", res);
>>> ? return 0;
>>> }
>>>
>>> Best
>>> Tomas
>>>
>>>
>>>>
>>>> Thanks
>>>> Tomas
>>>>
>>>>>
>>>>> Grateful for the attention,,
>>>>>
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
>>>>> 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: "Tomas Kalibera" <tomas.kalibera at
gmail.com>
>>>>> Para: "jcfaria" <joseclaudio.faria at
gmail.com>; "Duncan Murdoch"
>>>>> <murdoch.duncan at gmail.com>; r-devel at
r-project.org
>>>>> Enviado(s): 06/05/2022 04:24:44
>>>>> Assunto: Re: [Rd] Rgui.exe 4.2.0 does not receive
characters via
>>>>> the Windows API's PostMessage function
>>>>>
>>>>>>
>>>>>> On 5/6/22 07:03, jcfaria wrote:
>>>>>>> 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.
>>>>>>
>>>>>> I can't provide a good guess what impacted your
use, but if you
>>>>>> could give me a full example, ideally in C, which can
be compiled
>>>>>> with Rtools42 (so gcc, MinGW) and I can edit/recompile,
and works
>>>>>> with R 4.1, I am happy to help debugging on 4.2.
>>>>>>
>>>>>> Rgui now uses GraphApp Unicode windows on systems where
it didn't
>>>>>> before, because it uses UTF-8 also on systems it
didn't before
>>>>>> (on systems that would use a single-byte locale in R
4.1). These
>>>>>> Unicode windows are a different code path and there may
be bugs
>>>>>> not reported previously, including processing inputs
(recently I
>>>>>> fixed handling of accents, for example). Otherwise
indeed R now
>>>>>> uses UTF-8 as native encoding and UCRT as the C
runtime.
>>>>>>
>>>>>> Best
>>>>>> Tomas
>>>>>>
>>>>>>
>>>>>>>
>>>>>>> >
>>>>>>> >
>>>>>>>
>>>>>>> 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]]
>>>>>>>>>
>>>>>>>>>
______________________________________________
>>>>>>>>> R-devel at r-project.org mailing list
>>>>>>>>>
https://stat.ethz.ch/mailman/listinfo/r-devel
>>>>>>>>
>>>>>>>
>>>>>>> ______________________________________________
>>>>>>> R-devel at r-project.org mailing list
>>>>>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>>>>
>

On 5/16/22 19:21, Tomas Kalibera wrote:
> Dear Jose,
>
> On 5/15/22 01:31, jcfaria wrote:
>> Dear Tomas,
>>
>> I am very grateful for your attention!
>>
>> I've been reading some things about the GraphApp 
>> toolkit(http://enchantia.com/software/graphapp/) that is being used 
>> in the development of new versions of Rgui.
>>
>> Really, if it's a matter of choice, the problems I reported cannot
be
>> considered a "bug". It's up to us - GUI and IDE
application
>> developers - to adapt to the new features.
>>
>> I'm studying how to get around the problem, but I still haven't
found
>> a simple way.
>>
>> The solution you proposed (code below) ran fine here in all versions 
>> of Rgui I have installed, but it's working only for very simple 
>> strings, like the one I tested. When testing the needs close to the 
>> real I found some problems.
>>
>> For example, when sending the string below:
>> - char *s = "(s <- c('?', 'b', 'c',
'?'))";
>>
>> Rgui receives:
>> > 9s ,- c9'', 'b', 'c', ''00
>> Error: unexpected symbol in "9s"
>> >
>>
>>
>> #include <windows.h>
>> #include <stdio.h>
>> #include <string.h>
>>
>> int main(int argc, char **argv) {
>> ?? HWND hw;
>> ?? int i, res;
>>
>> ?? printf("Getting Rgui window...\n");
>> ?? hw = FindWindow(NULL, "R Console (64-bit)");
>>
>> ?? printf("Got window: %x\n", hw);
>> ?? if (hw == NULL) {
>> ???? printf("Could not get Rgui window: %x\n",
GetLastError());
>> ???? return 2;
>> ?? }
>>
>> ?? //Samples to send:
>> // char *s = "sd";
>> ?? char *s = "(s <- c('?', 'b', 'c',
'?'))";
>>
>> ?? for(i = 0; i < strlen(s); i++) {
>> ???? res = PostMessage(hw, WM_KEYDOWN, VkKeyScan(s[i]), 0);
>> ???? printf("Sending char %c: %d.\n", s[i], res);
>> ?? }
>>
>> ?? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
>> ?? printf("Sending return: %d\n.", res);
>> ?? return 0;
>> }
>>
>> The idea of Tinn-R communicating with Rgui.exe is to take advantage 
>> of the great stability of Rgui. Since communication with Rterm is 
>> done via pipe.
>>
>> I believe that developing a new interface using the resources of the 
>> R.dll library, as proposed, is outside the simple purposes of the 
>> Tinn-R project.
>>
>> Any help in this regard is welcome.
>
> If embedding R seems too involved, and the hack above doesn't work 
> well enough, perhaps you could use SendInput() (also mentioned in the 
> blog post [1] below as a more correct way to inject input as 
> WM_KEYDOWN).? This is an example:
>
> ---
>
> #include <windows.h>
> #include <stdio.h>
>
> int main(int argc, char **argv) {
> ? HWND hw, ow;
> ? int i, res;
>
> ? hw = FindWindow(NULL, "R Console (64-bit)");
> ? if (hw == NULL) {
> ??? printf("Could not get Rgui window: %x\n", GetLastError());
> ??? return 2;
> ? }
>
> ? ow = GetForegroundWindow();
> ? if (ow == NULL)
> ??? printf("Foreground window is NULL\n");
>
> ? if (!SetForegroundWindow(hw))
> ??? printf("Could not set Rgui as foreground window\n");
>
> ? char *sd = "sd";
> ? for(i = 0; i < strlen(sd); i++) {
> ??? INPUT input;
>
> ??? ZeroMemory(&input, sizeof(INPUT));
> ??? input.type = INPUT_KEYBOARD;
> ??? input.ki.dwFlags = KEYEVENTF_UNICODE;
> ??? input.ki.wScan = (unsigned) sd[i];
> ??? res = SendInput(1, &input, sizeof(INPUT));
>
> ??? printf("Sending char %c (%x): %d.\n", sd[i], sd[i], res);
> ? }
>
> ? {
> ??? INPUT input[2];
>
> ??? ZeroMemory(input, 2*sizeof(INPUT));
> ??? input[0].type = input[1].type = INPUT_KEYBOARD;
> ??? input[1].ki.dwFlags = KEYEVENTF_KEYUP;
> ??? input[0].ki.wVk = input[1].ki.wVk = VK_RETURN;
> ??? res = SendInput(2, input, sizeof(INPUT));
> ??? printf("Sending return: %d.\n", res);
> ? }
>
> ? if (!SetForegroundWindow(ow))
> ??? printf("Could not set the original window as foreground");
>
> ? return 0;
> }
Dear Jose,

to send non-ASCII and repeated characters, you can modify the loop above 
as follows (use wchar_t to send Unicode characters, send also 
KEYEVENTF_KEYUP events to ensure that repeated characters such as ')' in
the example are received). Otherwise, please refer to the MSDN 
documentation.

 ? wchar_t *sd = L"(s <- c('?', 'b', 'c',
'?'))";
 ? for(i = 0; i < wcslen(sd); i++) {
 ??? INPUT input;

 ??? ZeroMemory(&input, sizeof(INPUT));
 ??? input.type = INPUT_KEYBOARD;
 ??? input.ki.dwFlags = KEYEVENTF_UNICODE;
 ??? input.ki.wScan = (unsigned) sd[i];
 ??? res1 = SendInput(1, &input, sizeof(INPUT));

 ??? ZeroMemory(&input, sizeof(INPUT));
 ??? input.type = INPUT_KEYBOARD;
 ??? input.ki.dwFlags = KEYEVENTF_UNICODE | KEYEVENTF_KEYUP;
 ??? input.ki.wScan = (unsigned) sd[i];
 ??? res2 = SendInput(1, &input, sizeof(INPUT));

 ??? printf("Sending char %lc (%x): %d,%d .\n", sd[i], sd[i], res1,
res2);
 ? }

Best
Tomas
>
> ---
>
> This example works for me with R 4.1.3 and with R-devel 82368. It 
> doesn't work with R 4.2.0 (see a related thread about Dasher on this 
> list).
>
> Best
> Tomas
>
>>
>> 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: "Tomas Kalibera" <tomas.kalibera at gmail.com>
>> Para: "jcfaria" <joseclaudio.faria at gmail.com>;
"Duncan Murdoch"
>> <murdoch.duncan at gmail.com>; r-devel at r-project.org
>> Enviado(s): 11/05/2022 13:32:23
>> Assunto: Re: [Rd] Rgui.exe 4.2.0 does not receive characters via the 
>> Windows API's PostMessage function
>>
>>>
>>> On 5/11/22 15:39, Tomas Kalibera wrote:
>>>>
>>>> On 5/11/22 08:15, Tomas Kalibera wrote:
>>>>>
>>>>> On 5/11/22 03:02, jcfaria wrote:
>>>>>> Dear Tomas,
>>>>>> I've tried, but I don't have the necessary
C/C++ programming
>>>>>> skills to fulfill your request.
>>>>>>
>>>>>> Maybe someone can help us by transcribing the little
code in
>>>>>> object Pascal that I sent to C/C++.
>>>>>>
>>>>>> If a small executable, made in Object Pascal, can help
in your
>>>>>> debug, I can provide.
>>>>>
>>>>> Dear Jose,
>>>>>
>>>>> no problem, I can try out with the Pascal code.
>>>>> Is there a free compiler I can use to build and run it?
>>>>
>>>> Actually I can reproduce it in a C program doing the same
thing.
>>>>
>>>> The primary cause is that Rgui is using GraphApp Unicode
windows on
>>>> systems running in a multi-byte locale, which affects most
systems
>>>> since R 4.2 because of the switch to UTF-8. While Unicode
windows
>>>> have been used even in older versions of R, it was only on
systems
>>>> then running in a multi-byte locale, and apparently this
hasn't
>>>> been reported.
>>>>
>>>> When I modify R-devel to use non-Unicode GraphApp windows, the 
>>>> message sending works again. I will have a closer look, thanks
for
>>>> the report.
>>>
>>> I had a closer look and this doesn't really seem to be a bug in
R to
>>> me. For Unicode Windows, GraphApp uses WM_IME_COMPOSITION messages 
>>> to read the keys instead of WM_CHAR, which it uses for non-Unicode 
>>> windows. This is internal functionality of Rgui and a legitimate 
>>> choice. Rgui cannot simply handle both messages in Unicode windows,
>>> because the characters would be doubled (if you see an easy,
elegant
>>> change to Rgui that would mimic the previous behavior, let me
know).
>>> This is certainly not a documented interface for Rgui, so I am 
>>> afraid you would have to change something in your application.
>>>
>>> I read that using PostMessage to simulate keyboard input is 
>>> considered wrong, see [1], and then one should instead use
SendInput
>>> (which then requires bringing the window to the foreground), if at 
>>> all simulating keyboard input. Maybe one could create a better 
>>> working solution that way, or using some automation library.
>>>
>>> As a quick hack, I found that [2] happens to be working on my 
>>> system, but again relying on the current implementation of Rgui 
>>> (simply you send WM_KEYDOWN also for the characters other than the 
>>> newline/return). It seems to be working also with R 4.1 for me.
>>>
>>> The usual way for GUIs/front-ends is to "embed" R, to
link it as a
>>> DLL. Rgui itself does it and also external applications such as 
>>> RStudio. Typically you would want to have a thin layer application 
>>> embedding R and make your GUI communicate with that, but switching 
>>> to that from sending the messages would require some work.
>>>
>>> Best
>>> Tomas
>>>
>>> [1] https://devblogs.microsoft.com/oldnewthing/20050530-11/?p=35513
>>>
>>> [2]
>>> #include <windows.h>
>>> #include <stdio.h>
>>> #include <string.h>
>>>
>>> int main(int argc, char **argv) {
>>> ? HWND hw;
>>> ? int i, res;
>>>
>>> ? printf("Getting Rgui window...\n");
>>> ? hw = FindWindow(NULL, "R Console (64-bit)");
>>>
>>> ? printf("Got window: %x\n", hw);
>>> ? if (hw == NULL) {
>>> ??? printf("Could not get Rgui window: %x\n",
GetLastError());
>>> ??? return 2;
>>> ? }
>>>
>>> ? char *sd = "sd";
>>> ? for(i = 0; i < strlen(sd); i++) {
>>> ??? res = PostMessage(hw, WM_KEYDOWN, VkKeyScan(sd[i]), 0);
>>> ??? printf("Sending char %c: %d.\n", sd[i], res);
>>> ? }
>>>
>>> ? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
>>> ? printf("Sending return: %d\n.", res);
>>> ? return 0;
>>> }
>>>
>>>
>>>>
>>>> For reference, to reproduce I ran
>>>>
>>>> Rgui --sdi
>>>>
>>>> and used this C example:
>>>>
>>>> #include <windows.h>
>>>> #include <stdio.h>
>>>> #include <string.h>
>>>>
>>>> int main(int argc, char **argv) {
>>>> ? HWND hw;
>>>> ? int i, res;
>>>>
>>>> ? printf("Getting Rgui window...\n");
>>>> ? hw = FindWindow(NULL, "R Console (64-bit)");
>>>>
>>>> ? printf("Got window: %x\n", hw);
>>>> ? if (hw == NULL) {
>>>> ??? printf("Could not get Rgui window: %x\n",
GetLastError());
>>>> ??? return 2;
>>>> ? }
>>>>
>>>> ? char *sd = "sd";
>>>> ? for(i = 0; i < strlen(sd); i++) {
>>>> ??? res = PostMessage(hw, WM_CHAR, (unsigned int) sd[i], 0);
>>>> ??? printf("Sending char %c: %d.\n", sd[i], res);
>>>> ? }
>>>>
>>>> ? res = PostMessage(hw, WM_KEYDOWN, VK_RETURN, 0);
>>>> ? printf("Sending return: %d\n.", res);
>>>> ? return 0;
>>>> }
>>>>
>>>> Best
>>>> Tomas
>>>>
>>>>
>>>>>
>>>>> Thanks
>>>>> Tomas
>>>>>
>>>>>>
>>>>>> Grateful for the attention,,
>>>>>>
///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\///\\\
>>>>>> 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: "Tomas Kalibera" <tomas.kalibera at
gmail.com>
>>>>>> Para: "jcfaria" <joseclaudio.faria at
gmail.com>; "Duncan Murdoch"
>>>>>> <murdoch.duncan at gmail.com>; r-devel at
r-project.org
>>>>>> Enviado(s): 06/05/2022 04:24:44
>>>>>> Assunto: Re: [Rd] Rgui.exe 4.2.0 does not receive
characters via
>>>>>> the Windows API's PostMessage function
>>>>>>
>>>>>>>
>>>>>>> On 5/6/22 07:03, jcfaria wrote:
>>>>>>>> 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.
>>>>>>>
>>>>>>> I can't provide a good guess what impacted your
use, but if you
>>>>>>> could give me a full example, ideally in C, which
can be
>>>>>>> compiled with Rtools42 (so gcc, MinGW) and I can
edit/recompile,
>>>>>>> and works with R 4.1, I am happy to help debugging
on 4.2.
>>>>>>>
>>>>>>> Rgui now uses GraphApp Unicode windows on systems
where it
>>>>>>> didn't before, because it uses UTF-8 also on
systems it didn't
>>>>>>> before (on systems that would use a single-byte
locale in R
>>>>>>> 4.1). These Unicode windows are a different code
path and there
>>>>>>> may be bugs not reported previously, including
processing inputs
>>>>>>> (recently I fixed handling of accents, for
example). Otherwise
>>>>>>> indeed R now uses UTF-8 as native encoding and UCRT
as the C
>>>>>>> runtime.
>>>>>>>
>>>>>>> Best
>>>>>>> Tomas
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> >
>>>>>>>> >
>>>>>>>>
>>>>>>>> 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]]
>>>>>>>>>>
>>>>>>>>>>
______________________________________________
>>>>>>>>>> R-devel at r-project.org mailing list
>>>>>>>>>>
https://stat.ethz.ch/mailman/listinfo/r-devel
>>>>>>>>>
>>>>>>>>
>>>>>>>> ______________________________________________
>>>>>>>> R-devel at r-project.org mailing list
>>>>>>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>>>>>
>>