Windows Development

Re: Previewing files within an application

28-Apr-20 22:51

I have not done this myself, but I have used other functions in The Windows Shell - Win32 apps | Microsoft Docs[^]. Take a look to see if there is anything there that might help.

JudyL_MD30-Apr-20 7:05

JudyL_MD

30-Apr-20 7:05

You can do it in C#, and yes, you have to do your own registry searches. I can't remember if it had to call down into the Win32 API to do it or not. Unfortunately, the code I wrote (three years ago) that does this is on a network in a building that is closed right now so I can't take a peek and refresh my memory. It wasn't too hard, as I recall, but you do need to roll your own.

Be wary of strong drink. It can make you shoot at tax collectors - and miss.
Lazarus Long, "Time Enough For Love" by Robert A. Heinlein

SendInput mouse/keyboard and TouchScreen

Member 142257573-Mar-20 4:34

Member 14225757

3-Mar-20 4:34

Hello,

First of all, sorry for my English ^^

I'm blocked a problem with sending messages with SendInput and touch screens

Here is the detail of the problem :

I have an application that recovers touch inputs in Raw with "RegisterRawInputDevices"

Then I translate these entries into gestures such as a pan, scale in/out etc ...

Then, using gestures, I send mouse / keyboard messages with SendInput

The problem is that there is an system on the Windows side that does much the same thing, and it conflicts with my application.

For example, when I make a movement with 2 fingers on the touch screen, I send a mouse movement message with the average of the 2 points as position (see image)

<a href="https://ibb.co/DRxPfXp">ex1 — ImgBB</a>

The cursor is therefore positioned between my 2 fingers (green) but from time to time the cursor jumps to one of the 2 fingers (red)

It seems that the problem is related to <a href="https://docs.microsoft.com/fr-fr/windows/uwp/design/input/pen-and-stylus-interactions">wispv

I tried the technique indicate <a href="https://stackoverflow.com/questions/5120890/how-to-turn-off-all-touch-input-at-application-window-or-control-level/5128991#5128991">here</a>.
The TouchGate registry no longer exists in "Ordinateur\HKEY_CURRENT_USER\Software\Microsoft\Wisp\Touch"

But it is present here : Ordinateur\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Wisp\Touch

If I set the TouchGate value to 0 and restart the computer, this partly solves my problem because Windows no longer adds messages and I still have touch inputs from the Raw

The problem is that this technique requires a restart of the computer and that it is applied on the whole system whereas in the ideal I would only like to remove this layer for certain applications

I obviously tried to add this value in HKEY_CURRENT_USER and also tested the technique of updating windows with "SendMessageTimeout" and the message "WM_SETTINGCHANGE" but without success

Summary of my request

How to remove the system (wisp) or others multi touch overlay of Windows, dynamically (without restarting the machine)

Re: SendInput mouse/keyboard and TouchScreen

Randor 15-Aug-20 9:06

Randor

15-Aug-20 9:06

Hi,

Member 14225757 wrote:
How to remove the system (wisp) or others multi touch overlay of Windows, dynamically (without restarting the machine)

I believe that TouchGate is implemented as a low altitude HID filter driver. The operating system will want to reboot to remove it from the chain. Even if you used the SetupAPI to remove it... a reboot is still recommeneded.

Best Wishes,
-David Delaune

DNS query with winsock was failed

Eugene Pustovoyt12-Feb-20 4:35

12-Feb-20 4:35

Hi, everybody
I understand winsock has gethostbyname for this. But I need to debug for embedded application and first I try the code on Windows. Here is a my code:

C++

sockaddr_in dns_addr;
int dns_size = sizeof(dns_addr);
ZeroMemory(&dns_addr, dns_size);
dns_addr.sin_family = AF_INET;
dns_addr.sin_port = htons(53);
dns_addr.sin_addr.s_addr = inet_addr("8.8.8.8");

SOCKET out = socket(AF_INET, SOCK_DGRAM, 0);

char msg[] = {
    0x12, 0x34,         // ID
    0x01, 0x00,         // QR ... RCODE
    0x00, 0x01,         // QDCOUNT
    0x00, 0x00,         // ANCOUNT
    0x00, 0x00,         // NSCOUNT
    0x00, 0x00,         // ARCOUNT
    0x03,
    0x77, 0x77, 0x77,       // www
    0x03,
    0x74, 0x75, 0x74,       // tut
    0x02,
    0x62, 0x79,         // by
    0x00,
    0x00, 0x01,         // TYPE_A
    0x00, 0x01          // CLASS_IN
};
int msg_size = sizeof(msg);
int iSendOk = sendto(out, msg, msg_size, 0, (sockaddr*)&dns_addr, dns_size);

if (iSendOk != SOCKET_ERROR)
{
    char bufstr[100];
    sockaddr_in dest_addr;
    int dest_addr_size = sizeof(dest_addr);
    int iReceived = recvfrom(out, bufstr, 100, 0,(sockaddr*)&dest_addr, &dest_addr_size);
}

closesocket(out);

And this code freezes when recvfrom function is execution. The function is executed with an infinite loop and never returns. What do I do wrong?

Eugene Pustovoyt
Soft and Hard Developer

CPPMessageBox v1.0
CPPToolTip v2.1
CPPDumpCtrl v1.2
CPPHtmlStatic v1.2

Gerry Schmitz12-Feb-20 10:06

Gerry Schmitz

12-Feb-20 10:06

sockaddr_in dns_addr;
int dns_size = sizeof(dns_addr);

What's the "size" of the "uninitialized" dns_addr?

What other values can iSendOk take if it isn't SOCKET_ERROR?

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

Eugene Pustovoyt12-Feb-20 21:48

12-Feb-20 21:48

You're right. Getting size of structure better after initialization. But in my cause this structure has constant length and her size will be same after initialization.
Second, I check other returning values but I cut this code for this example. When I'm debugging this code sendto function return 28. This value is equal to the length of sent data.

Eugene Pustovoyt
Soft and Hard Developer

CPPMessageBox v1.0
CPPToolTip v2.1
CPPDumpCtrl v1.2
CPPHtmlStatic v1.2

Richard MacCutchan12-Feb-20 21:58

12-Feb-20 21:58

It is most likely that the remote device is not responding to the datagram. If there is no data to be read from the socket then recvfrom will block forever, or until the connection is broken. You should use a non-blocking method to check whether any data has been received and use some form of timed loop to allow the program to abort the activity after a fixed time period. See recvfrom function (winsock.h) - Win32 apps | Microsoft Docs[^] for full details.

Eugene Pustovoyt12-Feb-20 22:04

12-Feb-20 22:04

I tried to specify the reading size to 1 byte instead 100 from example. But I got same result.

Eugene Pustovoyt
Soft and Hard Developer

CPPMessageBox v1.0
CPPToolTip v2.1
CPPDumpCtrl v1.2
CPPHtmlStatic v1.2

Richard MacCutchan12-Feb-20 23:27

12-Feb-20 23:27

Of course you did. The socket is still waiting for a response from the remote address.

Eugene Pustovoyt12-Feb-20 23:35

12-Feb-20 23:35

Does it mean that the DNS server does not respond if there is not a single byte in response? But why?

Eugene Pustovoyt
Soft and Hard Developer

CPPMessageBox v1.0
CPPToolTip v2.1
CPPDumpCtrl v1.2
CPPHtmlStatic v1.2

Richard MacCutchan12-Feb-20 23:49

12-Feb-20 23:49

That server is owned by Google, so you should check with them how to get information from it. I am not sure that direct messages are accepted. See Get Started - Public DNS - Google Developers[^]

Obtaining HINTERNET Handles

Randor 15-Aug-20 9:19

Randor

15-Aug-20 9:19

Hi,

The code you posted is implemented as a blocking socket. It will literally block the entire thread until it receives a response from the other side.

To avoid this you can set the SO_RCVTIMEO[^] socket option.

Best Wishes,
-David Delaune

ForNow11-Feb-20 3:15

11-Feb-20 3:15

Would anyone know how to obtain a HINTERNET handle I tried OpenInternet included wininet.h but got errors as there were #define openinternet openinternetW and the compiler said openinternetW not defined even though I saw the function prototype in wininet.h

thanks

Richard MacCutchan11-Feb-20 5:26

11-Feb-20 5:26

I just looked at Wininet.h and there is no reference to OpenInternet, and neither Google nor MSDN appear to know about it. Which version are you working with?

ForNow11-Feb-20 5:53

11-Feb-20 5:53

Sorry my mistake its InternetOpen regardless intelisense is giving me a error #define internetOpen internetOpenW and internetOpenW is not defined

However looking at winInet.h

C++

INTERNETAPI_(HINTERNET) InternetOpenA(
    _In_opt_ LPCSTR lpszAgent,
    _In_ DWORD dwAccessType,
    _In_opt_ LPCSTR lpszProxy,
    _In_opt_ LPCSTR lpszProxyBypass,
    _In_ DWORD dwFlags
    );
INTERNETAPI_(HINTERNET) InternetOpenW(
    _In_opt_ LPCWSTR lpszAgent,
    _In_ DWORD dwAccessType,
    _In_opt_ LPCWSTR lpszProxy,
    _In_opt_ LPCWSTR lpszProxyBypass,
    _In_ DWORD dwFlags
    );
#ifdef UNICODE
#define InternetOpen  InternetOpenW
#else
#define InternetOpen  InternetOpenA
#endif // !UNICODE

Whether my property page settings are Unicode or Multicharacter I still get the same error

Thanks

Richard MacCutchan11-Feb-20 8:18

11-Feb-20 8:18

OK, I found it, and compiling with a call to InternetOpen() works fine. You need to gather, and show us, more information.

ForNow11-Feb-20 9:11

11-Feb-20 9:11

just started console application to see how I can obtain the FTP directory . one of the params was a HINTERNET handle

This is the code As for the property pages as I can not attach a picture I can only read off what I think is relevant

use of MFC - use standard windows libraries

Character Set Use Unicode character set

Windows SDK Version 10.0.17763.0

C++

#include "pch.h"
#include <iostream>
#include "winInet.h"
int main()
{
    std::cout << "Hello World!\n"; 
	InternetOpen("DBGR", INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, INTERNET_FLAG_ASYNC);
}

This was the include directory generated by Visual Studio

Quote:
C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\VC\Tools\MSVC\14.16.27023\include
C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\VC\Tools\MSVC\14.16.27023\atlmfc\include
C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\VS\include
C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\ucrt
C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\um
C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\shared
C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\winrt
C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\cppwinrt
C:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\Include\um

Richard MacCutchan11-Feb-20 9:37

11-Feb-20 9:37

This is a console application so it will be missing lots of definitions. You need to include windows.h before any of the other include files.

ForNow11-Feb-20 10:26