Needing assistance with pointers

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  1. #1
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    Needing assistance with pointers

    Hey, I'm trying to break in to my OWN computer so I can make it more secure and develop skills but I am getting confused with pointers...
    Code:
    #include <iostream>
    #include <windows.h>
    #define cmd.exe "C;\windows\system32\cmd.exe"
    using namespace std;
    int main()
    {
        char *Input[128];
        char Command[128];
        Input=&Command;
        cin>>Command;
        cout<<*Input;
        Command="MSG.exe * Hi";
        system("cmd.exe"+" "+Command);
    
    
    }
    Is there also any other way I can substitute system() for winexec()?

  2. #2
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    i don't know abt the later half of ur code , but u can improve the first half quite a lot ..
    Code:
    #include <iostream.h>
    #include <stdio.h>
    using namespace std;
    int main(){
        char Command[128];
        cin.get(Command,128);
        cout<<Command;
        return 0;
    }

  3. #3
    System Novice siavoshkc's Avatar
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    You don't need to use pointer there. Your program will not even compile. You should do it this way:
    Code:
    #include <iostream>
    #include <cstdlib>
    using namespace std;
    int main()
    {
    	char input[128];
    	cout<<"Enter command> ";
    	cin>>input;
    	system(input);
    	return 0;
    }
    Last edited by siavoshkc; 03-01-2006 at 09:32 AM.
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  4. #4
    Devil's Advocate SlyMaelstrom's Avatar
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    agarwaga, it's great that you know about the std namespace, but it really doesn't help to use it if you aren't using libraries that are defined under that namespace. <iostream.h> should be <iostream>, <stdio.h> should be <cstdio>, and siavoshkc, <stdlib.h> should be <cstdlib>
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  5. #5
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    i am returning back to C++ after quite some time ...

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    i want to use pointers though, yes their is an easier way of doing it, but i am not challenged from that

  7. #7
    System Novice siavoshkc's Avatar
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    With pointer:
    Code:
    #include <iostream>
    #include <cstdlib>
    using namespace std;
    int main()
    {
             char input[128];
             char* ptr=&input[0];
             cout<<"Enter command> ";
             cin>>ptr;
             system(ptr);
             return 0;
    }
    Or better:
    Code:
    int main()
    {
              char *ptr = new char[128];
              cout<<"Enter command> ";
              cin>>ptr;
              system(ptr);
              return 0;
    }
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  8. #8
    semi-colon generator ChaosEngine's Avatar
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    Quote Originally Posted by siavoshkc
    With pointer:
    Code:
    #include <iostream>
    #include <cstdlib>
    using namespace std;
    int main()
    {
             char input[128];
             char* ptr=&input[0];
             cout<<"Enter command> ";
             cin>>ptr;
             system(ptr);
             return 0;
    }
    Or better:
    Code:
    int main()
    {
              char *ptr = new char[128];
              cout<<"Enter command> ";
              cin>>ptr;
              system(ptr);
              return 0;
    }
    better still
    Code:
    #include <iostream>
    #include <string>
    #include <cstdlib>
    using namespace std;
    int main()
    {
             string input;
             cout<<"Enter command> ";
             cin>>input;
             system(input.c_str());
             return 0;
    }
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  9. #9
    System Novice siavoshkc's Avatar
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    Try using pointers, ChaosEngine.
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  10. #10
    semi-colon generator ChaosEngine's Avatar
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    Quote Originally Posted by siavoshkc
    Try using pointers, ChaosEngine.
    No. Pointers are completely unneccessary for this task. Anytime you can avoid them, you should. C++ provides several features (references, auto_ptr, vector, string) to avoid using pointers, which are notoriously error-prone.

    Learn to use them.
    "I saw a sign that said 'Drink Canada Dry', so I started"
    -- Brendan Behan

    Free Compiler: Visual C++ 2005 Express
    If you program in C++, you need Boost. You should also know how to use the Standard Library (STL). Want to make games? After reading this, I don't like WxWidgets anymore. Want to add some scripting to your App?

  11. #11
    System Novice siavoshkc's Avatar
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    Yes, but starter of the thread wants to practice pointers I think. Look at the posts before sending new one please.
    i want to use pointers though, yes their is an easier way of doing it, but i am not challenged from that
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  12. #12
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    I believe there are better ways to learn pointers than the problem given For example, the OP could learn pointers by creating his own linked list (something which inevitably all programmers end up doing at least once in their lives)

  13. #13
    System Novice siavoshkc's Avatar
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    I agree. pointer should be used in its own place, minimum required.
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  14. #14
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    Quote Originally Posted by bikr692002
    Hey, I'm trying to break in to my OWN computer so I can make it more secure and develop skills but I am getting confused with pointers...
    Code:
    #include <iostream>
    #include <windows.h>
    #define cmd.exe "C;\windows\system32\cmd.exe" // improper format 1
    using namespace std;
    int main()
    {
        char *Input[128];  // problem #2
        char Command[128];
        Input=&Command; 
        cin>>Command;
        cout<<*Input;
        Command="MSG.exe * Hi";
        system("cmd.exe"+" "+Command);  // problem #3
    
    
    }
    Is there also any other way I can substitute system() for winexec()?
    #1
    #define cmd.exe "C;\windows\system32\cmd.exe"
    the . is illegal, cmd is not a structure
    the ; should be :
    each \ should be \\

    #2
    char *Input[128];
    why create 128 pointers? simply
    char *Input;
    should suffice.

    #3
    system("cmd.exe"+" "+Command);
    character arrays cannot be added. Use strcat() to combine them then call the function.

    Other errors can be fixed after these, unless everyone else has pulled you away from fixing your original project.
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    tics meaning blood sucking parasites
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  15. #15
    System Novice siavoshkc's Avatar
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    There are more errors than those.
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