Question

I have a program where i ask the user for the name of a text file, I open the text file do stuff with it (read, write), then I close the file and exit the program.

Program.h

class Program
{
     char* fileName;
public:
     Program();
     ~Program();
     void ReadFile(void);
};

Program.cpp

Program::Program(){
     //contstructor
     fileName=NULL;
}

Program::~Program(){
     cout << "in destructor" ;
     delete []fileName;
}

void Program::ReadFile(void){
     fileName = new char[40];

     cout <<"Please enter the name of the file to open: ";
     cin.clear();
     cin.getline(fileName, 40);

     ifstream file (fileName);

     if(file.is_open()){
          //do stuff
     }
     file.close();
}

right now when I put delete []fileName; in the destructor it outputs “”in destructor” on the screen but fileName does not get deleted. If I take delete []fileName; and put it in ReadFile() after file.close() fileName gets deleted. Why is that?

The rest of my program works perfectly which is why none of that code is pasted. I am just trying to rid any memory leaks and fileName is the only one I am having trouble with so therefore I only pasted the code where fileName is used.

Any help is appreciated.

Additional information:
I am using Visual Studio to write this and am using the Memory Leak Detection. This is what it outputs:

Detected memory leaks!
Dumping objects ->
{132} normal block at 0x005D49A0, 40 bytes long.
Data: 6E 61 6D 65 73 2E 74 78 74 00 CD CD CD CD CD CD
Object dump complete.
The program ‘[10772] program1.exe: Native’ has exited with code 0 (0x0).

which is why I suspect delete []fileName; didn’t work.

also, this is what the int main() looks like

int main(){
     Program abc;
     abc.ReadFile();
}

Oh, and Program.h can not be changed. Only .cpp can be change it’s part of my requirements.

Answer 1

Are you sure your main is exactly as posted here? If you just define abc globally, it will be freed after memory dump report memory leaks and you may see invalid reports! You can insert a break point in the destructor and see if memory leaks reported after or before destructor