onexit.c and my bad programming style

[UMCPmatt]

int *i;

i is a pointer to an integer. What does i point to? Nothing, as we have not initialized that variable. There is no integer at that point, thus you cannot say something like *i=123; because i points to undefined memory. If you did the following:
int j;
i=&j;

but could I say

&i=&j

???

Then i is a pointer to j. You could of course dynamically allocate some memory as well:

int *i=new int;
or
int *i = malloc(sizeof(int));

ok that makes sense

The point is that

int *i;

is certainly not a shortcut for

int i;
&i;

Regarding your code excerpt, every MFC application has a class derived from CWinApp which contains the application's entry point. CWinApp is derived from CWinThread - after all, your main instance is just your application's primary thread. CWinThread contains the m_pMainWnd data member.


what do I need to include so that my source file SEES m_pMainWnd?


Dan East
[/quote]

[Dan East]

[UMCP_matt]

[angedelamort]

[UMCP_matt]

i seem to be getting confused cause I forget about how x is intialized..

so when I see

&x I ALWAYS tihnk address of x

but i think this is only the case if x is initialized like

int x;

but if it is intialized like

int *x

THEN x is ALREADY the address so saying &x makes no sense..

am I getting it?

I use pointers all the time I am hoping once I really understand what I am doing everything will make more sense.

so

char *x

x is the address that contains the character

so to assign it a value I say

*x = 'c';

yes?

what if I wanted a string.. I would say

*x = "something";

and

x[3] = 'e';

right?

[Digby]

You're still confused (and wrong) in your assumptions.

int *x;

&x certainly makes sense. It's taking the address of a pointer variable that points to an int.

In your other case:

char *x;

*x = 'c';

This is horrible as you're storing the character 'c' into an unknown memory address that most certainly doesn't belong to your application. "Oh bartender, another pint of 0xC0000005 Access Violation please..."

The best thing for you to do is to write some simple lines of C code assigning values to various variables and then look at the values in the debugger and the memory watch window when you step through your app until you understand what is happening.

[angedelamort]

[Dan East]

[UMCP_matt]