C / C++ / MFC

FirstPrevNext

Difference between New and Malloc ? 15-Oct-01 22:40 15-Oct-01 22:40  I noticed in various program loops that allocating a buffer with the new operator didn't seem to work each time. I mean it did work but partially, I sometime have partially allocated buffers (?). This: char* pBuf = new char[iVariable]; is not safe. When iVariable is a constant, like MAX_PATH it always succeed but not when it has a dynamic value. I admit, I seldom test if the allocation succeded or not but the buffer is always allocated but not on the entire sequence (?). Maybe doesn't the new operator allocate contiguous memory blocks and then a pointer operation (pBuf++) is not safe ? Then, I wonder when I should use malloc instead of new to get sure the buffer is allocated ? Yarp Re: Difference between New and Malloc ? markkuk16-Oct-01 1:04 markkuk 16-Oct-01 1:04  malloc() is for C programs, new is for C++ programs. You can never be sure that your allocation succeeds, always check the result! If the allocation succeeds, the memory block is always contiguous and the size you requested. Re: Difference between New and Malloc ? Tomasz Sowinski16-Oct-01 1:21 Tomasz Sowinski 16-Oct-01 1:21  malloc() is for C programs, new is for C++ programs. This is too strict. One can safely use malloc/free in C++ program. Just don't mix malloc with delete and new wih free - what was allocated with new should be deallocated with delete, malloc() should be accompanied by free(). Tomasz Sowinski -- http://www.shooltz.com Re: Difference between New and Malloc ? Tomasz Sowinski16-Oct-01 1:10 Tomasz Sowinski 16-Oct-01 1:10  char* pBuf = new char[iVariable]; is safe, at least when iVariable is correctly initialized. If iVariable contains bogus bits, the buffer size may be too large to fit on the heap. In such case, operator new fails and returns NULL on VC6 or throws bad_alloc exception on standard-conforming compilers. the buffer is always allocated but not on the entire sequence (?). I don't understand what do you mean. Maybe doesn't the new operator allocate contiguous memory blocks It allocates contiguos block of size passed in iVariable. Tomasz Sowinski -- http://www.shooltz.com Re: Difference between New and Malloc ? 16-Oct-01 5:53 16-Oct-01 5:53  Hi, thank you all for replying. the buffer is always allocated but not on the entire sequence (?). I mean that I was reading a file buffer and I read the beginning of the buffer but the buffer is empty before the end of it, so I suppose it was partially initialized. Yarp Re: found out the problem yarp16-Oct-01 8:31 yarp 16-Oct-01 8:31  I found out the problem: iVariable ;(( I used the size of another -smaller- disk file (i used it to load a file buffer in memory). The "smaller" makes all difference and actually did the partial buffer load that I noticed. Anyway, I'm now sure that new and malloc have the same usage and that they both create contiguous memory buffer. Sorry and thanks ) Yarp Register my OLE/COM object 15-Oct-01 22:00 15-Oct-01 22:00  In OLE/COM Object viewer My object present in the folder : Automation Objects but if I try open it by press on the + , I gets the messageBox: ------------------------ CoGetClassObject failed class not registered REGDB_E_CLASSNOTREG(..) ------------------------ I try to register it again by: regsvr32 <dll filename=""> but I get error message that the LoadLibrary failed . (the path is clearly ok !). What can I do ? Re: Register my OLE/COM object Christian Graus15-Oct-01 22:45 Christian Graus 15-Oct-01 22:45  According to MSDN Q. What are the reasons an ATL server might fail to register? The following also applies to ATL 3.0: A. The following are the top three reasons an ATL server might fail to register: You built your project with _WIN32_WINNT=0x400 (the default), and you are not running the ATL server under Windows NT 4.0 or you do not have an up-to-date version of Oleaut32.dll. To solve this problem, run "DUMPBIN /EXPORTS OLEAUT32.DLL" and search for UnregisterTypelib. If it is not there, then your server cannot run. Remove this #define statement from Stdafx.h if you want to run the ATL server under Windows 95 or older versions of Windows NT. Alternatively, you can use LoadLibrary and GetProcAddress so that you can run optimally under both Windows 95 and Windows NT 4.0. The Oleaut32.dll that ships with the Internet Explorer 3.x is up-to-date. You built your project as MinSize and Atl.dll is not properly installed on the system. The correct version of Atl.dll must be copied and registered by Regsvr32. There are Windows NT and Windows 95 versions of Atl.dll. The Windows 95 version runs under Windows NT. However, since it does not use the UNICODE APIs, it is slightly less efficient. Unless you build your project as MinDependency, you will need to install the correct version of Atl.dll and run Regsvr32 on it before you install your server. You built your project as UNICODE, and you cannot run it under Windows 95. The following are the steps to troubleshoot: For a DLL server, run Regsvr32 in the debugger. Open the Project Settings dialog box and click the Debug tab. In the Executable for debug session text box, enter the full path to Regsvr32.exe, such as C:\Sharedide\Bin\Regsvr32.exe. In the Program arguments text box, specify the full path to your DLL, such as C:\Myprojects\MyFolder\Debug\MyFile.dll. Set a breakpoint at DllRegisterServer and start stepping. For an EXE server, run it in the debugger and specify /REGSVR as its command-line argument. I suggest if you need to ask this question again tomorrow you try to provide some more information, because it's obvious based on what you're asking that either you're not providing enough info, or you have got the right answers and want to hear something else. Have you got your books yet ? Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. thank you ! Can you explain me some things ? 15-Oct-01 23:18 15-Oct-01 23:18  thank you So this is what I understant from all this : *For the DLL server* ----------------------- Open the Project Settings -Debug tab. In the Executable for debug session text box, enter the path to Regsvr32.exe and In the Program arguments text box, specify the full path to my DLL. Is that all ? * I have windows98 Re: thank you ! Can you explain me some things ? Christian Graus15-Oct-01 23:46 Christian Graus 15-Oct-01 23:46  To be honest I opened MSDN and looked for something that sounded helpful. What the above is going to do is pass the dll path as the argument to RegSrv32, it's the same as navigating to the dll path and typing regsrv32 mydll.dll in the console. If you don't have access to MSDN, try msdn.microsoft.com, there are a lot of articles that matched my search, you might find something more helpful there. Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. Register my OLE/COM object 15-Oct-01 23:40 15-Oct-01 23:40  I tried it and I gets again the errorMessage that it failed ! I dont understand where exactly I have put a breakpoint (What means "at DllRegisterServer" ???) Re: Register my OLE/COM object Christian Graus16-Oct-01 0:20 Christian Graus 16-Oct-01 0:20  If you don't have a dllRegisterServer function, then RegSrv32 is obviously not going to work. Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. excuse me ! It was stupid ! but- 16-Oct-01 0:36 16-Oct-01 0:36  excuse me , I found this function and I put in breakpoint but the debug dont arrived to this func. I needs help urgently with my poblem !!!!!!! I dont success to register my dll !!!!!!! Re: excuse me ! It was stupid ! but- Michael P Butler16-Oct-01 0:43 Michael P Butler 16-Oct-01 0:43  What compile option have you used for your ATL DLL? Is it Min-Dependencys or Min-Size? Michael excuse me ! I didnt understand you ! 16-Oct-01 0:53 16-Oct-01 0:53  Can you explain me what means Min-Dependencys or Min-Size ? I simply compile with f5 ,f7, ctlf7 Re: excuse me ! I didnt understand you ! Christian Graus16-Oct-01 1:22 Christian Graus 16-Oct-01 1:22  When you choose the configuration to compile, you can choose minimum dependancy or minimum size. What they mean is a no brainer - one compiles to include all the code it needs, the other leaves out whatever it can to keep the size down. I believe this function is one you loose in min size, because there are other ways to register, but the details escapec me. Mimi, if you logged in I would have got an email telling me you responded to my comment and I would have been able to reply sooner. Not that the other comment is no good, chances are he knows more about it than me, but I'm trying to point out the benefits of logging in. After two weeks of the same questions we all know it's you, so if you were hoping to be anonymous, you'll have to ask about something else ;0) Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. Re: excuse me ! I didnt understand you ! #realJSOP16-Oct-01 1:28 #realJSOP 16-Oct-01 1:28  He's having promblems spelling "anonymous" too. To hell with those thin-skinned pillow-biters. - Me, 10/03/2001 How to get the width and height of a window? (MFC) 15-Oct-01 21:10 15-Oct-01 21:10  I wanna know the width and height of a window in pixels!? How to? / |------ \ Re: How to get the width and height of a window? (MFC) PJ Arends15-Oct-01 21:15 PJ Arends 15-Oct-01 21:15  Client area -> GetClientRect() whole window (borders, caption) -> GetWindowRect() --- Blessed are those who can laugh at themselves, for they shall never cease to be amused Re: How to get the width and height of a window? (MFC) Michael Dunn15-Oct-01 21:16 Michael Dunn 15-Oct-01 21:16  CRect rc; cwnd.GetClientRect ( &rc ); rc.right is the width, and rc.bottom is the height. --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and Re: How to get the width and height of a window? (MFC) Braulio Dez16-Oct-01 3:21 Braulio Dez 16-Oct-01 3:21  Normally GetClienRect() would work fine, if it doesn´t give you the size in pixels you have to change the viewport HTH Braulio Re: How to get the width and height of a window? (MFC) JerzyPeter16-Oct-01 6:43 JerzyPeter 16-Oct-01 6:43  CRect rect; GetWindowRect(&rect); int nWidth=rect.Width(); int nHeight=rect.Height(); Jerzy Non VC - But Help greatly appriciated - working with InstallShields Statbat15-Oct-01 20:25 Statbat 15-Oct-01 20:25  Hi, I have made a database application using VC++ this database application connects to the Microsoft Access file via ODBC. I want to create an installshield setup to install this software on client system. I don't know how install shields can create a new User DataSource (in ODBC in ControlPanel) so that installed application can run properly. Any help or hint or what so ever is welcome Thanks for ur time ..... ~Statbat( ); Re: Non VC - But Help greatly appriciated - working with InstallShields 16-Oct-01 1:08 16-Oct-01 1:08  I have dont some setup application using Installshield.It is very very easy and selfexplanatory.do u have Installshield installed in ur system.u can mail me for additional help.my email id is ujustmailme@email.com. bye Re: Non VC - But Help greatly appriciated - working with InstallShields Not Active16-Oct-01 1:57 Not Active 16-Oct-01 1:57  There are two ways you can do this. Installshield has an ODBC wizard, or you can create the registry entries from a script. What version of Installshield are you using?

Last Visit: 31-Dec-99 18:00     Last Update: 1-Jul-24 10:33 Refresh ᐊ Prev1...17883178841788517886178871788817889178901789117892 Next ᐅ

General    News    Suggestion    Question    Bug    Answer    Joke    Praise    Rant    Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.