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  • Can I draw Qt objects directly to Win32 DC (Device Context)?

    - by Kevin
    I can draw Qt objects to an QImage and then draw the image to HDC or CDC. This may hurt our application's performance. It would be great if I can draw Qt objects directly to Win32 HDC or MFC CDC. I expect that there is a class, say QWin32Image for clear, then I can use it in this way: QWin32Image image(hdc, 100, 100, Format_ARGB32_Premultiplied); QPainter painter(&image); painter.drawText(....); Is it possible for my thought? Or is there a better way to do that?

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  • Which Win32 API reports the Format preference in the Region and Language control panel?

    - by Integer Poet
    Windows 7 and Windows Vista have a Region and Language control panel which contains a Formats tab which contains a popup menu titled Format. This menu allows the user to select from among many language-oriented sets of number, currency, time, and date formatting preferences regardless of the language of the base system. For example, I could decide I prefer the default currency symbol to be Japanese yen on a US English system. The Windows Contacts application changes its behavior depending on these format preferences. For example, if I select Japanese formatting preferences, Windows Contacts displays and lets me edit phonetic names (AKA "ruby", "yomi", and "furigana") but not middle names. If I select US English formatting preferences, Windows Contacts displays and lets me edit middle names but not phonetic names. I need to write code (native C calling Win32) which mirrors the behavior of the Windows Contacts application in this respect. Which API should I call?

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  • How can I change text on a win32 window?

    - by Will
    Looking for hints, tips and search terms for changing the text on a win32 window from C#. More specifically, I'm trying to change the text on the print dialog from "Print" to "OK", as I am using the dialog to create a print ticket and not do any printing. How can I find the dialog's window handle? Once I've got it, how would I go about finding the button in the child windows of the form? Once I've found that, how would I change the text on the button? And how can I do all this before the dialog is shown? There's a similar question here, but it points to a CodeProject article that is waaay more complex than needed and is taking me a bit longer to parse through than I'd like to spend on this. TIA.

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  • (win32) What to do when a file remains left open when a remote application crashes or forgets to clo

    - by Stephane R.
    Hi I have not worked so much with files: I am wondering about possible issues with accessing remote files on another computer. What if the distant application crashes and doesn't close the file ? My aim is to use this win32 function: HFILE WINAPI OpenFile(LPCSTR lpFileName, LPOFSTRUCT lpReOpenBuff, UINT uStyle); Using the flag OF_SHARE_EXCLUSIVE assures me that any concurrent access will be denied (because several machines are writing to this file from time to time). But what if the file is left open ? (application crash for example ?) How to put the file back to normal ?

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  • Why are some strings displayed as garbage when I scroll my read-only multiline Win32 edit control ve

    - by sharptooth
    In my native C+ Win32 GUI application I have a property sheet with two property pages. One of the property pages contains an edit box: EDITTEXT IDC_EDIT_ID,x,y,width,height,ES_MULTILINE | ES_READONLY | NOT WS_BORDER | WS_VSCROLL | WS_HSCROLL | NOT WS_TABSTOP,WS_EX_STATICEDGE I set a multiline text to this edit box. The text has more lines than the edit can fit, so some of the text is clipped and a vertical scroll bar appears. When I scroll up with the mouse the lines that come "from under clip area" are drawn as garbage - it looks like first one line is drawn, then some other line is drawn on the same place without first painting the background. The lines that just move up - ones that were visible before scrolling and remain visible after scrolling are displayed allright. What's the reason and workaround for this behavior?

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  • Why does the Win32-API have so many custom types?

    - by sub
    I'm new to the Win32 API and the many new types begin to confuse me. Some functions take 1-2 ints and 3 UINTS as arguments. Why can't they just use ints? What are UINTS? Then, there are those other types: DWORD LPCWSTR LPBOOL Again, I think the "primitive" C types would be enough - why introduce 100 new types? This one was a pain: WCHAR* I had to iterate through it and push_back every character to an std::string as there wasn't another way to convert it to one. Horrible. Why WCHAR? Why reinvent the wheel? They could have just used char* instead, or?

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  • How to Compile Mod_Python 3.3.1 for Python 2.6 and Apache 2.2 on Windows?

    - by John
    I have no experience compiling code other than using Visual Studio's Build command. I am hoping we can create a step by step guide for compiling mod_python on windows. Please be as descriptive as possible. This is what I've done so far: Download and install python 2.6.2 Download and install apache 2.2.11 Download the most recent source code for mod_python from svn From here I'm lost to what the next step is. I've downloaded Microsoft Visual C++ 2008 Express Edition. As mentioned by Hao I've already tried the tutorial mentioned in that link. Here is the error messages I'm receiving with that tutorial. C:\mod_python\distbuild_installer.bat Could Not Find C:\mod_python\src*.obj running bdist_wininst running build running build_py creating build creating build\lib.win32-2.6 creating build\lib.win32-2.6\mod_python copying C:\mod_python\lib\python\mod_python\apache.py - build\lib.win32-2.6\mod _python copying C:\mod_python\lib\python\mod_python\cache.py - build\lib.win32-2.6\mod_ python copying C:\mod_python\lib\python\mod_python\cgihandler.py - build\lib.win32-2.6 \mod_python copying C:\mod_python\lib\python\mod_python\Cookie.py - build\lib.win32-2.6\mod _python copying C:\mod_python\lib\python\mod_python\importer.py - build\lib.win32-2.6\m od_python copying C:\mod_python\lib\python\mod_python\psp.py - build\lib.win32-2.6\mod_py thon copying C:\mod_python\lib\python\mod_python\publisher.py - build\lib.win32-2.6\ mod_python copying C:\mod_python\lib\python\mod_python\python22.py - build\lib.win32-2.6\m od_python copying C:\mod_python\lib\python\mod_python\Session.py - build\lib.win32-2.6\mo d_python copying C:\mod_python\lib\python\mod_python\testhandler.py - build\lib.win32-2. 6\mod_python copying C:\mod_python\lib\python\mod_python\util.py - build\lib.win32-2.6\mod_p ython copying C:\mod_python\lib\python\mod_python__init__.py - build\lib.win32-2.6\m od_python running build_ext building 'mod_python_so' extension creating build\temp.win32-2.6 creating build\temp.win32-2.6\Release creating build\temp.win32-2.6\Release\mod_python creating build\temp.win32-2.6\Release\mod_python\src C:\Program Files\Microsoft Visual Studio 9.0\VC\BIN\cl.exe /c /nologo /Ox /MD /W 3 /GS- /DNDEBUG -DWIN32 -DNDEBUG -D_WINDOWS -IC:\mod_python\src\include -Ic:\apa che\include -IC:\Python26\include -IC:\Python26\PC /TcC:\mod_python\src\mod_pyth on.c /Fobuild\temp.win32-2.6\Release\mod_python\src\mod_python.obj mod_python.c c:\apache\include\ap_config.h(25) : fatal error C1083: Cannot open include file: 'apr.h': No such file or directory error: command '"C:\Program Files\Microsoft Visual Studio 9.0\VC\BIN\cl.exe"' fa iled with exit status 2

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  • Programmatically closing a dialog box - win32 [migrated]

    - by user1697579
    I'm working on an application to detect a pop-up dialog and then automatically dismiss it. I'm writing this as a C++/Win32 app. The dialog box is generated by IE 7 and I can detect the window, but several methods to get the OK button to "click" have failed. Doing searches for other people's solutions, sending these messages to the button handle seems to have worked in a lot of situations: PostMessage( handle, WM_LBUTTONDOWN, 0, 0 ); PostMessage( handle, WM_LBUTTONUP, 0, 0 ); PostMessage( handle, BM_SETSTATE, 1, 0 ); It has no effect on the button state in my tests though. I can send tab characters to the main window and see that the OK button gets focus, but then sending return characters does nothing. To learn more about this I used Spy++ to get information about the window hierarchy and what messages are delievered when I manually click the OK button. Looking at the message log and reading about WM_MOUSEACTIVATE seamed to offer a solution. The log info shows that 0002166C was the button window. So in my code I tried this: GetClassNameA( handle, str, str_size ); if( strcmp( str, "Internet Explorer_Server" ) != 0 ) return TRUE; // Not the window we're interested in. // Send a message to activate the button window and have it process a mouse click. PostMessage( handle, WM_MOUSEACTIVATE, (WPARAM) dialog_handle, MAKELPARAM( HTCLIENT, WM_LBUTTONDOWN ); Based on the window hierarchy and message log, I think the window with the class name "Internet Explorer_Server" is the button. Maybe I'm wrong, because it does seem like an odd class name for a button... Below is a link to the window hierarchy image, message log when I manually click the OK button. Last is the code that's executed on a 1 second timer ticket, looking for the window. Any insight and help is appreciated! Image of the window hierarchy, source, window messages, and test dialog source are available here: https://sites.google.com/site/matthewmillersmiscellanea/Home/

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  • C++/Win32 : XP Visual Styles - no controls are showing up?

    - by mrl33t
    Okay, so i'm pretty new to C++ & the Windows API and i'm just writing a small application. I wanted my application to make use of visual styles in both XP, Vista and Windows 7 so I added this line to the top of my code: #pragma comment(linker,"\"/manifestdependency:type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"") It seemed to work perfectly on my Windows 7 machine and also Vista machine. But when I tried the application on XP the application wouldn't load any controls (e.g. buttons, labels etc.) - not even messageboxes would display. This image shows a small test application which i've just put together to demonstrate what i'm trying to explain: http://img704.imageshack.us/img704/2250/myapp.png In this test application i'm not using any particularly fancy or complicated code. I've effectively just taken the most basic sample code from the MSDN Library (http://msdn.microsoft.com/en-us/library/ff381409.aspx) and added a section to the WM_CREATE message to create a button: MyBtn = CreateWindow(L"Button", L"My Button", BS_PUSHBUTTON | WS_CHILD | WS_VISIBLE, 25, 25, 100, 30, hWnd, NULL, hInst, 0); But I just can't figure out what's going on and why its not working. Any ideas guys? Thank you in advanced. (By the way the application works in XP if i remove the manifest section from the top - obviously without visual styles though. I should also probably mention that the app was built using Visual C++ 2010 Express on a Windows 7 machine - if that makes a difference?)

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  • SWT applet: swt-win32-3650.dll already loaded in another classloader

    - by kilonet
    I have multiple pages with java applet written with SWT. The problem is, applet loads only on first page, to load it on another page i need restart browser, otherwise i get following error: Exception in thread "Thread-27" java.lang.UnsatisfiedLinkError: Could not load SWT library. Reasons: no swt-win32-3650 in java.library.path no swt-win32 in java.library.path Native Library C:\Documents and Settings\xxx\Local Settings\Temp\swtlib-32\swt-win32-3650.dll already loaded in another classloader C:\Documents and Settings\xxx\Local Settings\Temp\swtlib-32\swt-win32.dll: %1 is not a valid Win32 application at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source) at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source) at org.eclipse.swt.internal.C.<clinit>(Unknown Source) at org.eclipse.swt.widgets.Display.<clinit>(Unknown Source) I wonder, how can I unload swt dlls when browser page with applet is closed?

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  • How To Get The Outout of Win32::Process command in perl

    - by rockyurock
    hello all, i am using "use Win32::Process" for my application run as below, it runs fine but i did not get any way to get the output to a .txt file. i used NORMAL_PRIORITY_CLASS rather than CREATE_NEW_CONSOLE to get the output on the same terminal itself but i don't know how to redirect it to a txt file. /rocky !/usr/bin/perl use strict; use warnings; use Win32::Process; Win32::Process::Create(my $ProcessObj, "iperf.exe", "iperf.exe -u -s -p 5001", 0, NORMAL_PRIORITY_CLASS, ".") || die ErrorReport(); my @command_output; push @command_output,$ProcessObj; open FILE, "zz.txt" or die $!; print FILE @command_output; close FILE; sleep 10; $ProcessObj-Kill(0); sub ErrorReport{ print Win32::FormatMessage( Win32::GetLastError() ); }

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  • Making an interface for input in C - How?

    - by tloszk
    I have a big question. I started to develop a simple 3D engine (or should I call it framework?). I use OpenGL for rendering and it is developed for Windows. It is all written in C. But I don't know, how to write an "interface" for the keyboard/mouse input. I would like to keep it as simple as possible and nice - what the Win32 "native" input system is not. If anyone has suggestions about the topic, please, tell me. Thanks for everyone, who answers to my question!

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  • Win32 and Win64 programming in C sources?

    - by Nick Rosencrantz
    I'm learning OpenGL with C and that makes me include the windows.h file in my project. I'd like to look at some more specific windows functions and I wonder if you can cite some good sources for learning the basics of Win32 and Win64 programming in C (or C++). I use MS Visual C++ and I prefer to stick with C even though much of the Windows API seems to be C++. I'd like my program to be portable and using some platform-indepedent graphics library like OpenGL I could make my program portable with some slight changes for window management. Could you direct me with some pointers to books or www links where I can find more info? I've already studied the OpenGL red book and the C programming language, what I'm looking for is the platform-dependent stuff and how to handle that since I run both Linux and Windows where I find the development environment Visual Studio is pretty good but the debugger gdb is not available on windows so it's a trade off which environment i'll choose in the end - Linux with gcc or Windows with MSVC. Here is the program that draws a graphics primitive with some use of windows.h This program is also runnable on Linux without changing the code that actually draws the graphics primitive: #include <windows.h> #include <gl/gl.h> LRESULT CALLBACK WindowProc(HWND, UINT, WPARAM, LPARAM); void EnableOpenGL(HWND hwnd, HDC*, HGLRC*); void DisableOpenGL(HWND, HDC, HGLRC); int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { WNDCLASSEX wcex; HWND hwnd; HDC hDC; HGLRC hRC; MSG msg; BOOL bQuit = FALSE; float theta = 0.0f; /* register window class */ wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_OWNDC; wcex.lpfnWndProc = WindowProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH); wcex.lpszMenuName = NULL; wcex.lpszClassName = "GLSample"; wcex.hIconSm = LoadIcon(NULL, IDI_APPLICATION);; if (!RegisterClassEx(&wcex)) return 0; /* create main window */ hwnd = CreateWindowEx(0, "GLSample", "OpenGL Sample", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 256, 256, NULL, NULL, hInstance, NULL); ShowWindow(hwnd, nCmdShow); /* enable OpenGL for the window */ EnableOpenGL(hwnd, &hDC, &hRC); /* program main loop */ while (!bQuit) { /* check for messages */ if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { /* handle or dispatch messages */ if (msg.message == WM_QUIT) { bQuit = TRUE; } else { TranslateMessage(&msg); DispatchMessage(&msg); } } else { /* OpenGL animation code goes here */ glClearColor(0.0f, 0.0f, 0.0f, 0.0f); glClear(GL_COLOR_BUFFER_BIT); glPushMatrix(); glRotatef(theta, 0.0f, 0.0f, 1.0f); glBegin(GL_TRIANGLES); glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.0f, 1.0f); glColor3f(0.0f, 1.0f, 0.0f); glVertex2f(0.87f, -0.5f); glColor3f(0.0f, 0.0f, 1.0f); glVertex2f(-0.87f, -0.5f); glEnd(); glPopMatrix(); SwapBuffers(hDC); theta += 1.0f; Sleep (1); } } /* shutdown OpenGL */ DisableOpenGL(hwnd, hDC, hRC); /* destroy the window explicitly */ DestroyWindow(hwnd); return msg.wParam; } LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) { switch (uMsg) { case WM_CLOSE: PostQuitMessage(0); break; case WM_DESTROY: return 0; case WM_KEYDOWN: { switch (wParam) { case VK_ESCAPE: PostQuitMessage(0); break; } } break; default: return DefWindowProc(hwnd, uMsg, wParam, lParam); } return 0; } void EnableOpenGL(HWND hwnd, HDC* hDC, HGLRC* hRC) { PIXELFORMATDESCRIPTOR pfd; int iFormat; /* get the device context (DC) */ *hDC = GetDC(hwnd); /* set the pixel format for the DC */ ZeroMemory(&pfd, sizeof(pfd)); pfd.nSize = sizeof(pfd); pfd.nVersion = 1; pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER; pfd.iPixelType = PFD_TYPE_RGBA; pfd.cColorBits = 24; pfd.cDepthBits = 16; pfd.iLayerType = PFD_MAIN_PLANE; iFormat = ChoosePixelFormat(*hDC, &pfd); SetPixelFormat(*hDC, iFormat, &pfd); /* create and enable the render context (RC) */ *hRC = wglCreateContext(*hDC); wglMakeCurrent(*hDC, *hRC); } void DisableOpenGL (HWND hwnd, HDC hDC, HGLRC hRC) { wglMakeCurrent(NULL, NULL); wglDeleteContext(hRC); ReleaseDC(hwnd, hDC); }

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  • IIS logs show sc-win32-status=64 but only through some networks

    - by wweicker
    I have an ASP.NET application running on a client server (W2k3, IIS6, .NET 2.0). FWIW, this is a Test instance, it hasn't been moved into Production yet. So it is not running under SSL, load balancing, etc. When I access one of the pages on their server from our office, the page gets hit once. Inspecting the IIS logs (c:WINDOWS\system32\LogFiles\W3SVC1) show a GET for that page, then I push a button on the page and the log file shows a POST. This seems to be working fine so far. Now when I remote into the client's network and access the page from one of their local machines, the log file shows a GET, then I push the button on the page and the log shows two POSTs at the same second. The first one shows status (sc-status, sc-substatus, sc-win32-status) 200 0 64, the second shows 200 0 0. In the log file, both POSTs are identical. Basically the log looks like this (except I masked some of the data): #Fields: date time s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status sc-substatus sc-win32-status 2009-08-11 20:19:32 x.x.x.x GET /File.aspx - 80 - y.y.y.y Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.0;+WOW64;+Trident/4.0;+SLCC1;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.21022;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30618;+MDDR;+OfficeLiveConnector.1.4;+OfficeLivePatch.0.0) 200 0 0 2009-08-11 20:19:45 x.x.x.x POST /File.aspx - 80 - y.y.y.y Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.0;+WOW64;+Trident/4.0;+SLCC1;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.21022;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30618;+MDDR;+OfficeLiveConnector.1.4;+OfficeLivePatch.0.0) 200 0 64 2009-08-11 20:19:45 x.x.x.x POST /File.aspx - 80 - y.y.y.y Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.0;+WOW64;+Trident/4.0;+SLCC1;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.21022;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30618;+MDDR;+OfficeLiveConnector.1.4;+OfficeLivePatch.0.0) 200 0 0 The problem is, the page is getting hit twice. The database performs an operation for the first request, then the second request detects that a duplicate operation is being performed and throws an error message. The users think their operation failed, but it actually succeeded. The error description of sc-win32-status 64 is: "The specified network name is no longer available." This leads me to believe, given that both POST requests show an HTTP status of 200, that the server is successful in serving the request, but the client is never notified and resubmits the request. How can I troubleshoot this? Any ideas what could be causing this behavior on their internal network only? I should mention, this is happening at two separate client sites, but does not happen at six of our other client sites, or in our office, or connecting to any of our eight clients over the web. What could be making this reproducible 100% of the time on their local network but 0% of the time anywhere else? Update: I found a very small number of the duplicated POST requests had sc-win32-status of 995 instead of 64 as originally reported. The error description of sc-win32-status=995 is: "The I/O operation has been aborted because of either a thread exit or an application request." This doesn't make any sense (considering I have full access to the code). I still don't understand how or why this issue is occurring, but the new error code leads me to believe it may not be a network issue after all and I am now investigating the possibility of a random code bug.

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  • WPF HwndHost keyboard focus

    - by Adal
    The chart area in the screenshot is a HwndHost control which hosts a native Win32 window (with it's own registered WNDCLASS) implemented in C++/CLI and drawn with Direct2D. The HwndHost is hosted in a WPF Border control. The problem I have is that I can't set the keyboard focus to the hosted Win32 window. I want the focus to move to the hosted Win32 window when the used clicks on the chart area. I tried calling SetFocus on WM_LBUTTONDOWN, but that screws app the focus in the rest of the application. Currently, even if I click on the Win32 window, the focus remains on the tree-view on the left, and if I press the up/down cursor keys, the tree-view will get them, not the chart window. How do I make the hosted Win32 window receive keyboard input from when the user clicks on the chart area, until it clicks on another control (like the tree-view, or the toolbar)?

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  • Win32: Is there a replacement GDI32.dll that uses hardware acceleration?

    - by Ian Boyd
    Has anyone out there created a version of GDI32.dll that takes advantage of hardware acceleration available on the machine? gdiplus.dll? Starting with Windows Vista, GDI is no longer hardware accelerated. (GDI+ was never hardware accelerated). Without Microsoft fixing GDI (and GDI+) to be able to run well on the computer: native applications (C++ MFC, Delphi, etc), and managed WinForms applications, will continue to run poorly forever. While i could use Direct2D for business applications, i cannot control the fact that the development environment still creates controls, with decades of library support code, that assumes the presence of GDI.

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  • Win32: What is the status of chunked encoding support in WinHttpReadData?

    - by Cheeso
    The documentation for WinHttpReadData says, regarding HTTP's chunked transfer coding: Starting in Windows Vista and Windows Server 2008, WinHttp enables applications to perform chunked transfer encoding on data sent to the server. When the Transfer-Encoding header is present on the WinHttp response, WinHttpReadData strips the chunking information before giving the data to the application. Can anyone decipher this? Q1 First, this text is on the page for WinHttpReadData, which is used to ... read data within an HTTP client application, specifically the response data. So what does it mean when it says Starting in Windows Vista and Windows Server 2008, WinHttp enables applications to perform chunked transfer encoding on data sent to the server. The WinHttpReadData function isn't used with data being sent to the server. It is used when reading data from the server. Consulting the doc for the WinHttpWriteData function, which is used to send data to the server as part of an HTTP request, there is no mention of the chunked transfer capability. Q2 Supposing that I figure out just what the newish chunked transfer support amounts to, how do I get that support? It says that it is new on Vista and WS2008. What happens if I write an app that runs on WS2003, and uses WinHttpReadData and it encounters a chunked response, or WinHttpWriteData, and it wants to send a chunked request? Between the lines, is this documentation saying that I need to link against the Vista-era Windows SDK, or later, in order to get the capability to do chunked encoding? Or is it really impossible on WS2003?, in other words it is the case that the app doing chunked transfer using this library must run on the OS specified? This might read like a rant, but it's not. I truly want to know.

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  • According to MSDN ReadFile() Win32 function may incorrectly report read operation completion. When?

    - by Martin Dobšík
    The MSDN states in its description of ReadFile() function (http://msdn.microsoft.com/en-us/library/aa365467%28VS.85%29.aspx): “If hFile is opened with FILE_FLAG_OVERLAPPED, the lpOverlapped parameter must point to a valid and unique OVERLAPPED structure, otherwise the function can incorrectly report that the read operation is complete.” I have some applications that are violating the above recommendation and I would like to know the severity of the problem. I mean the program uses named pipe that has been created with FILE_FLAG_OVERLAPPED, but it reads from it using the following call: ReadFile(handle, &buf, n, &n_read, NULL); That means it passes NULL as the lpOverlapped parameter. That call should not work correctly in some circumstances according to documentation. I have spent a lot of time trying to reproduce the problem, but I was unable to! I always got all data in right place at right time. I was testing only Named Pipes though. Would anybody know when can I expect that ReadFile() will incorrectly return and report successful completion even the data are not yet in the buffer? What would have to happen in order to reproduce the problem? Does it happen with files, pipes, sockets, consoles, or other devices? Do I have to use particular version of OS? Or particular version of reading (like register the handle to I/O completion port)? Or particular synchronization of reading and writing processes/threads? Or when would that fail? It works for me :/ Please help! With regards Martin

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  • Can I use Win32 FreeType without the .dll file?

    - by Khatharr
    Hello. I'm teaching myself OpenGL and I'm implementing ttf text rendering using FreeType 2. I downloaded the library from http://gnuwin32.sourceforge.net/packages/freetype.htm and after a couple of minor issues I got it running properly. The thing that's bothering me is that I have to place a copy of freetype6.dll in the directory with my executable in order for the thing to run. I generally try to avoid a bunch of unnecessary dll files floating around. I'm sort of new to windows programming, but from what I understand most libraries can be built to run fully from a lib rather than requiring a dll at runtime. Looking through the documentation from FT is making my brain melt, so I thought I would ask here to see if there were any devs that have worked with FT before and if so, do they know how to build the library such that no dll is required at runtime. Thank you in advance for any advice or support.

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  • How to show percentage of 'memory used' in a win32 process?

    - by pj4533
    I know that memory usage is a very complex issue on Windows. I am trying to write a UI control for a large application that shows a 'percentage of memory used' number, in order to give the user an indication that it may be time to clear up some memory, or more likely restart the application. One implementation used ullAvailVirtual from MEMORYSTATUSEX as a base, then used HeapWalk() to walk the process heap looking for additional free memory. The HeapWalk() step was needed because we noticed that after a while of running the memory allocated and freed by the heap was never returned and reported by the ullAvailVirtual number. After hours of intensive working, the ullAvailVirtual number no longer would accurately report the amount of memory available. However, this method proved not ideal, due to occasional odd errors that HeapWalk() would return, even when the process heap was not corrupted. Further, since this is a UI control, the heap walking code was executing every 5-10 seconds. I tried contacting Microsoft about why HeapWalk() was failing, escalated a case via MSDN, but never got an answer other than "you probably shouldn't do that". So, as a second implementation, I used PagefileUsage from PROCESS_MEMORY_COUNTERS as a base. Then I used VirtualQueryEx to walk the virtual address space adding up all regions that weren't MEM_FREE and returned a value for GetMappedFileNameA(). My thinking was that the PageFileUsage was essentially 'private bytes' so if I added to that value the total size of the DLLs my process was using, it would be a good approximation of the amount of memory my process was using. This second method seems to (sorta) work, at least it doesn't cause crashes like the heap walker method. However, when both methods are enabled, the values are not the same. So one of the methods is wrong. So, StackOverflow world...how would you implement this? which method is more promising, or do you have a third, better method? should I go back to the original method, and further debug the odd errors? should I stay away from walking the heap every 5-10 seconds? Keep in mind the whole point is to indicate to the user that it is getting 'dangerous', and they should either free up memory or restart the application. Perhaps a 'percentage used' isn't the best solution to this problem? What is? Another idea I had was a color based system (red, yellow, green, which I could base on more factors than just a single number)

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  • How to change the toolbar controler's Bitmap in win32 ?

    - by Morpheus
    Hi all! I have created a toolbar with some controls on it using ReBar within a window. Can anyone please tell me, How to get the HWND of a controller if I know (only) the Id of it ? How to obtain the HBITMAP if I know the id of the resource ? How to set the bitmap to the controller ? SendDlgItemMessageW(hWnd, nId, BM_SETIMAGE, IMAGE_BITMAP, (LPARAM)hBitmap); This isn't working for toolbars, isn't it ? I couldn't find a way to do it, please help me. Thank you... Regards

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  • How to show the progressbar using threading functionality in win32?

    - by kiddo
    In my application I have a simple module were I will read files for some process that will take few seconds..so I thought of displaying a progress bar(using worker thread) while the files are in progress.I have created a thread (code shown below) and also I designed a dialog window with progress control.I used the function MyThreadFunction below to display the progressbar but it just shows only one time and disappears,I am not sure how to make it work.I tried my best inspite of the fact that I am new to threading.Please help me with this friends. reading files void ReadMyFiles() { for(int i = 0; i < fileCount ; fileCount++) { CWinThread* myThread = AfxBeginThread((AFX_THREADPROC)MyThreadFunction,NULL); tempState = *(checkState + index); if(tempCheckState == NOCHECKBOX) { //my operations } else//CHECKED or UNCHECKED { //myoperation } myThread->PostThreadMessage(WM_QUIT,NULL,NULL); } } thread functions UINT MyThreadFunction(LPARAM lparam) { HWND dialogWnd = CreateWindowEx(0,WC_DIALOG,L"Proccessing...",WS_OVERLAPPEDWINDOW|WS_VISIBLE, 600,300,280,120,NULL,NULL,NULL,NULL); HWND pBarWnd = CreateWindowEx(NULL,PROGRESS_CLASS,NULL,WS_CHILD|WS_VISIBLE|PBS_MARQUEE,40,20,200,20, dialogWnd,(HMENU)IDD_PROGRESS,NULL,NULL); MSG msg; PostMessage( pBarWnd, PBM_SETRANGE, 0, MAKELPARAM( 0, 100 ) ); PostMessage(pBarWnd,PBM_SETPOS,0,0); while(PeekMessage(&msg,NULL,NULL,NULL,PM_NOREMOVE)) { if(msg.message == WM_QUIT) { DestroyWindow(dialogWnd); return 1; } AfxGetThread()->PumpMessage(); Sleep(40); } return 1; }

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  • how can i install a service under a different account than the LocalSystem account using win32 api

    - by taher chhabrawala
    hi i am using the following code to install the service, i want to install this service under a different account, the last two parameters takes username and password but when i give so it throws an error...is there any specific way of giving username password here? IntPtr sv_handle = CreateService(sc_handle, svcName, svcDispName, SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL, svcPath, null, 0, null, null, null);

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