Programming :: Overriding Inherited Member Functions In C++ Vtable?
Aug 17, 2010
have an inherited base class that has some virtual members and I wish to overide these members in the derived class. So for example I have the following base class called B and the derived class called D. I will illustrate them both below. I am finding I get a linker error when making the project and cannot work out why this should be so.
Do you have any ideas why does wxHyperlinkCtrl doesn't work on Linux?It has an error which says..."/usr/include/wx-2.8/wx/gdicmn.h:215: undefined reference to 'vtable for wxHyperlinkCtrl'"Do I have to include a certain library so that it will work in Linux? I try to compile it in windows and its succesful.'m having a problem on Linux guysinitialize the wxHyperlinkCtrl like this... wxHyperlinkCtrl* hyperlink1 = new wxHyperlinkCtrl();and included #include <wx/hyperlink.h> Is there something missing on it?... I already had tried supplying parameters on the constructor but same thing it gives me an error
I am getting the following error:'auto_ptr' is not a member of 'std'This was working fine in gcc version 4.1.2 20080704 (Red Hat 4.1.2-48).After upgrading to gcc version 4.4.4 (GCC), it is NOT working.
The code below defines an array of structures in a class. I would like this to be a Static array and then initialize the array in a initialization method. I understand that initialization lists are the way to go but due to the size and complexity of the array I plan on using (the example below is a simple snippet that illustrates the problem) I would like to use the initialization method. However, I cant even get this thing to compile. The error says the reference to the ArrayOfStructs in the initialization routine is undefined.
l_long_Island
P.S. This is the error message
undefined reference to `ClassWithStaticArray::ArrayOfStruts'
class ClassWithStaticArray { public: struct IntegerStruct {
I have added new member "i_mymember" to inode on-disk structure in ext3_fs.h file and tried to access this in userspace program, but gives me error that "error: �struct ext3_inode� has no member named �i_mymember� "
i have trouble to define a static member in a template, and i search from google, but didn't find any similar case, my case is a little complex, i paste the code below.code in xxx.h
This may be a basic bash array/string operation related question, but I couldn't find any direct answer. So here it goes:I have a lot of data sorted in various directories. All directories need same processing except for a special group of directories. I have a symbolic link of the script in discussion in each directory. I want the script to get the name of the current directory, check if that belongs to special group and do specific operations.So I get the name of the directory
Code: mm=`basename `pwd`` Now the the group of directories that needs something different to be done, contains these
None of my daemon scripts work now, and the startup process displayed errors. Should I reinstall the OS and start from scratch, or is there a way to recover these files? Is there a way to rebuild the files I deleted?
Where are the definitions for C library functions located? It was just recently that I realized that header files don't actually define any functions, they merely include their prototypes.
For instance, stdio.h includes the following line:
Code:
This just means that the definition of printf() is located in another file. What file? Is there some kind of default shared object file that is automatically included during compilation?
I have problem to use an alias that defined in ksh93 script,in the functions in the same script onm Linux.I definied an alias in main: alias echo='echo -e' in order that echo will read backslashes but when i executed it in function, the alias didnt work, and performewd a regular echo, without -e
cat test.ksh #!/bin/ksh alias echo='echo -e' checkUsage
have an application where from time to time I need to check the db for some value and run some functions to do some checks. is the best option do it as php daemon or cron job?Whatworried of cron job is the overalapping.
Im implementing a chat application using Jabber/XMPP and gloox framework which should send and receive messages concurrently in Ubuntu Linux.
The problem faced is both the threads are created and pthread_join( ) is called for both.The iSend thread is scheduled first but gets suspended at cin. Once the recv( ) function is called, which runs in iRecv thread, the recv call back function handleMessage( ) is called. However the control never shifts back to the iSend thread which should call SendMessage( ) function.
I am trying to write a simple program in C that involves nesting switches. For example switch 1 offers an option to go to module 1 or 2 or quit. when I go to module 1 there is another switch function offering two or more choices.
I can select either module 1 or 2 at the start of the program and the selection text for, say, module 1 prints to screen but then exits without allowing a second selection to be entered.
I tried using free([first selection]) thinking that might do the trick but it doesn't.
Is it possible to next switches on after another in C?
But I would like to avoid this approach as there are a lot of places in my program where I would have to make this change. Can I perhaps rebuild the pthreads library on macos without affecting other apps ?
Let's show the problem: I have a socked connection (in a fd var). In certain moment, I need to use the same socket in two threads. Lets see in the example:
I have functions which return different data like: int, char*, double...
I also have a list of datatypes (INTEGER, TEXT, REAL...) which can be returned.
I need to map a datatype with function, which purpose is to return it. Therefore, when I determine a datatype, I would like to call the required function without doing switch all the time.
I feel like there should be a cleaner way of doing this. I have one file, for example "a.cpp", calling a function from another file, "b.cpp". Currently I have it set up so that header for "b", "b.h", has the declaration of its functions. And then I'm just including "b.h" in "a.cpp". Do I have to include the "b" header file in "a" to be able to call a function from "b"? Or is there a better way I could be doing this? Like doing something different at compile?
I've encountered a problem when running a simple bit of code, I'm using c to read write data to a binary file. It works fine when I run as root. However when I run as a user it produces the file, however when I try to open / write after it's produced it caused a seg fault. Is there any reason file functions ( fopen etc ) would work for root and not a user and is there a way to fix this?
I'm trying to call some kernel functions from userspace, but I'm not sure if I'm doing it right. The functions control a pulse width modulator on an embedded platform. To pick one at random, the function:
Code: struct pwm_device *pwm_request(int pwm_id, const char *label); is defined in linux/pwm.h, and the implementation uses the macro EXPORT_SYMBOL(pwm_request), so I should be able to call this from user-space... right?
Anyway, I've got linux/pwm.h to #include in my source so the compiler knows what it's doing, but what do I link against? The only place in by kernel build tree where I can see a symbol pwm_request defined is in object files like vmlinux.o, built-in.o in the directory, etc. which I don't think I should be linking against.