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Greetings:
This is probably the most sophomoric question I have ever posted but this situation constantly comes up for me and I would like to know what the accepted method is for resolving it:
I have created two structures. They can contain all manner of member data but each one contains a pointer of the OTHER structure type. I'm sure that made very little sense, so here's a simple example:
<br />
typedef struct<br />
{<br />
AnotherClass* pAN;<br />
} OneClass;<br />
<br />
typedef struct<br />
{<br />
OneClass* pOC;<br />
} AnotherClass;<br />
I'm using Visual Studio 2003. The compiler won't build this because the definition of "OneClass" includes a pointer to "AnotheClass". But "AnotherClass" is not defined yet. I assume that this is because the compiler compiles from the top down and doesn't know about "AnotherClass" when its trying to process "OneClass".
I'm pretty sure that there are classes out there that are part of large, professional level frameworks and libraries that contain these kinds of cyclical references and somehow the compiler doesn't seem to mind.
Correct me if I'm wrong...
Thank you,
Mark
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As the reference is to a pointer, you can just forward declare the other struct instead of an include. That is, something like
struct OneClass;
at the top of the AnotherClass definition file. Or if they are in the same file, just the one that's declared second can be forward declared at the top.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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This can be solved by a forward declaration. following code will compile.
typedef struct
{
struct AnotherClass;
AnotherClass* pAN;
} OneClass;
typedef struct
{
OneClass* pOC;
} AnotherClass;
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Hello,
Can anyone tell me which function I can use to delete all file in a folder. Any standard ANSI C++ function I can used? Thanks!
Nacho
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There are two solutions; one is to get all the files in the directory using findfirst/findnext and then delete them.
The other solution is to use the SHFileOperation.
Oh, I suppose you could spawn cmd and delete that way, but it's lame.
Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke
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Nacho Chip wrote: Any standard ANSI C++ function I can used?
No. This type of operation will be OS dependent, and will be very different on each system. For Windows, you can use the FindFile API or the Shell interfaces to accomplish this.
If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week
Zac
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See
<code>
WIN32_FIND_DATA find;
SetCurrentDirectory("c:\\temp");
HANDLE handle=FindFirstFile("*.*",&find);
while(FindNextFile(handle,&find)!=0)
DeleteFile(find.cFileName);
or you can use from
FindClose(handle);
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First of all, I'm a beginner.  Second, I make a program that should launch an EXE. Not just EXEs, but different games. Some of them launch, but most of them like Call of Duty, Vice City and others don't.Some games say, they cannon find some settings files, some just critical errors, CoD even shows a message that it has searched files in a wrong folder (should be "D:\games\Call of Duty - United Offensive\uo" but he searches in "D:\games\Call of Duty - United Offensive\uo/uo". I've tried all found functions except for CreateProcess. What can cause the problem?
-- modified at 17:26 Thursday 3rd August, 2006
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Well, AFAIK there are two main elements to watch when launching external programs:
. Current directory
. Parameters
If your games EXE relies on the current directory (which may affect the search path) or any given parameters, then that could be a reason.
Have a look at the properties of the launch shortcut to see what it is passing to the OS to launch the programs.
I Dream of Absolute Zero
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Well, now I know the reason: directory parameter of ShellExecute was NULL. Now all works (except for 1 game shows black screen only on loading). Thanks for reply.
-- modified at 10:38 Friday 4th August, 2006
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hi, i want to use ostream to write to a txt file, though i dont want it to automaticly start a new txt file, if a text file already excists, but behave similar as :
FILE* f=fopen("txt.txt","a");
fwrite(buffer,sizeof(buffer),1,f);
thanks
-- modified at 16:22 Thursday 3rd August, 2006
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FredrickNorge wrote: FILE* f=fopen("txt.txt","a");
fwrite(buffer,sizeof(buffer),1,f);
That isn't using ostream ...
If you want to use ostream (specifically, ofstream):
ofstream fout("file.txt", ios::out | ios::app);
fout << "Hello, world!" << endl;
That will open a file named "file.txt" for output and append "Hello, world!" to the end of the file.
If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week
Zac
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Hey guys,
The additional include directory in the project Im looking @ is listed as below
$(RTI_HOME)/$(RTI_BUILD_TYPE)/include
I am working with Windows OS but I'm still confused why it still works with $ sign
in front of the environment variables.
I thought ($) sign in front of environment variables is suppose to mean you are working
with a Linux/Unix environment and (%) sign in front of environment variables is
suppose to mean you are working with the Windows OS.
Someone help me out here.....
Thanks in advance
Jaysan
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it's not a Windows or Unix thing, it's a Visual Studio thing.
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($) is a Visual Studio thing?
then when do we use (%) and ($) while referring to different OS directories
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Jay03 wrote: ($) is a Visual Studio thing?
when you said "project", i assumed you were talking about VS. and VS uses $(name) for its configuration macros.
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I have an MFC app and I'd like to get notified whenever a any of several possible child windows recv focus. I thought I could just override the main window's PreTranslateMessage() function and simply check the pMsg->message value and if it's a WM_SETFOCUS and the pMsg->hWnd is one of the windows I care about then react accordingly. However I never get ANY WM_SETFOCUS messages!
Am I misunderstanding how PreTranslateMessage is supposed to be used or is there an alternate approach? I'd prefer not to have to subclass each of the controls, but I will if I have to.
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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AFAIK the WM_* messages are sent to the pMsg->hWnd window. If that window does not handle the message then it is sent to the parent of that window and on up the parent chain until one of the windows actually handles the message (returns TRUE), or the there are no more parent windows. So the only way the main window will get the WM_SETFOCUS message is if none of the child windows handle it, or they return false if they do.
See CWnd::WalkPretranslateTree() and AfxInternalPreTranslateMessage() in the MFC sources for more details (Set a breakpoint in your PreTranslateMessage() function and use the call stack)
You may be right
I may be crazy
-- Billy Joel --
Within you lies the power for good, use it!!!
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the problem is not from the way u try to catch the message, but from the message u want to catch, WM_SETFOCUS cound't be caught, I tried to catch it in the simplest window's program. catch this message before TranslateMessage calls, but still, couldn't get it. somebody knows why?
life is like a box of chocolate,you never know what you r going to get.
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Jim, did you get a solution for this without rewriting all your child controls?
You may find that setting up a WH_CALLWNDPROC hook is the easiest way to be notified when a window in your app recieves the WM_SETFOCUS message.
You may be right
I may be crazy
-- Billy Joel --
Within you lies the power for good, use it!!!
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No, in the end I just added the OnSetFocus() methods to the various controls.  Wasn't that big of a deal, just annoying. But then that pretty much sums up MFC development, for me at least
¡El diablo está en mis pantalones! ¡Mire, mire!
Real Mentats use only 100% pure, unfooled around with Sapho Juice(tm)!
SELECT * FROM User WHERE Clue > 0
0 rows returned
Save an Orange - Use the VCF!
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Hi
I have a windows based application and creates a icon on the system tray, i wanted to keep it active all the time ( i mean visible in the system tray). I know i can do this by going to taskbar properties-> customize notifications -> Always show, does any body know how to achieve this programmatically?
Thanks for help in advance
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Whenever the thump of the HScroll goes to the end of the scroll bar in the CListCtrl, I will add the 20 records in the listctrl. It will be attain by inserting the record at the HScroll method, by calculating the thump value. Whether the thump is getting to the end, then only I will add the records. But I met the problem which is When I track the thump to the end of the HScroll, the mouse holding the Thump. At the time I need to release the mouse from the holding of thump. I have tried by posting the message of WM_LBUTTONUP by the
SendMessage(WM_LBUTTONUP);
function. Please help me..
~ Selva
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If you need to release the mouse capture and stop scrolling, I think you can try this sequence:
SetCapture();
ReleaseCapture();
I hope it helps.
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