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Runtime Error: Warning about uninitialized variable

Posted on 2003-10-27
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Last Modified: 2010-07-27
Hi Experts,

I am trying to write the following code and have some trouble.  

#include <stdio.h>
typedef struct {
      int a;
      int b;
}Box;

void main()
{
    Box *myBox;
    myBox->a = 4;
}

I am getting this warning message when I compile: "local variable 'myBox' used without having been initialized "  and the program crashes when I run it.

How can I solve this problem?  How do I initialize this pointer??

Thanks
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Question by:g_jey
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1 Comment
 
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Accepted Solution

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n_fortynine earned 200 total points
ID: 9631176
what you have there is a pointer. without having been initialized means that it is not given any memory, i.e. the instance of your struct Box has not been created. so you have to do:
Box* myBox;
myBox = new Box;
then you can use it all you want.
just remember to delete it after you're done with the instance
delete myBox;
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