assign the value of an array to a pointer c++

This is a discussion on assign the value of an array to a pointer c++ within the C++ Programming forums, part of the General Programming Boards category; Hello @ all I`m trying to do the following: Code: pTest->tst[0] = user_tst[0]; content of array is at this index ...

  1. #1
    kox
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    Question assign the value of an array to a pointer c++

    Hello @ all
    I`m trying to do the following:

    Code:
    pTest->tst[0] = user_tst[0];
    content of array is at this index 0x00

    which doesn't work and stucks me to the following error:

    error C2109: subscript requires array or pointer type.

    the array comes from another file and is well defined(there) as it is also made external in the included header file.

    I would be glad, if anyone could give me a hint or point me to correct direction.

    Thanks for every read/help.

    kox
    Last edited by kox; 10-28-2012 at 06:56 PM. Reason: added code tags

  2. #2
    Registered User C_ntua's Avatar
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    Hey kox,
    I would say post a bit more code or the whole file if it is not to big, it is a bit hard to guess only with one line. Don't forget the code tags!

  3. #3
    kox
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    here you are (code snippets)

    thx for your reply

    here is the relevant code:
    file1 filling the array:

    Code:
    int tst_user[5];
    
    int Fill()
    {
        char variable[] = "";
        char * pch;
        int i = 0;
        
         
        printf("Enter desired Data in this style XX-XX-XX-XX-XX-XX : \n");
        scanf("%s", &variable); //user input to address of variable
        
        pch = strtok (variable, "- :");
        while (pch != NULL)
        {
            printf("%s \n",pch);  //control of splitting
            sscanf (pch, "%x", &tst_user[i]);  //filling
            pch = strtok (NULL, "- :");
            printf("array index %d = %#x \n",i, tst_user[i++]);   //control array and add 1 to index
        }
    
        return 0;
    }
    .
    .
    .
    Fill()
    .
    .
    .
    used header:

    Code:
    extern int tst_user;

    file 2 assigning the array to the pointer:

    Code:
    pTest->tst[0] = tst_user[0]);
    manually(static) assigning works just fine:

    Code:
    pTest->tst[0] = 0x00;
    but this is not what i want.

    The code is very long and the failure should be in the assignment or the interchange of the array itself.

    i also tried it with:
    Code:
    pTest->tst[0] = static_cast<int>(tst_user[0]);
    which gives the same error.

    Thanks for reading/helping

    kox
    Last edited by kox; 10-28-2012 at 06:58 PM. Reason: finer argumentation

  4. #4
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    perhaps show the definition for the class/structure of which pTest is an object.

  5. #5
    Algorithm Dissector iMalc's Avatar
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    So what does the definition of tst look like? The error is telling you that it's not an array or pointer, but you're using the square brackets as if it were a pointer.
    You should show the definition of pTest too. It might be that you actually want pTest[0]->tst.
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  6. #6
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    You have
    Code:
    extern int tst_user;
    and
    Code:
    int tst_user[5];
    Hmmm...

  7. #7
    kox
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    Hi @ all

    @ caligulaminus

    but when i do this :
    Code:
    extern int tst_user[5];
    i get an unresolved externals error;

    i think the definition and the making extern should be correct,
    it compiles... till i use the instance of the array.

    THX

    kox
    Last edited by kox; 10-29-2012 at 08:03 AM.

  8. #8
    kox
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    Hi @ all

    @ iMalc thx for your help

    The pointer is defined correctly, i tried some examples and figured out that the mistake is about the
    Code:
    tst_user[i]
    array.
    For any reason i cant re-use this in the second file.
    It seems that due to the interchange between the two files, the definition gets lost.

    Any ideas

    Thx

    kox
    Last edited by kox; 10-29-2012 at 08:28 AM.

  9. #9
    kox
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    problem is in sharing the array itself

    Hi @ all

    @ caligalimus
    Sorry, I have to correct myself,
    I think youre right, the correct making external should be with the index([5]).
    the array definition got lost cause i redefined it as an standard integer (without the index).
    So i think the compiler thinks it is an standard variable and therefore the type failure error.

    But in correct defining
    Code:
     extern int tst_user[5];
    there is the problem with the unresolved external, which i should focus on.

    error LNK2001: unresolved external symbol "int * tst_user" (?tst_user@@3PAHA)

    This says nothing to me and English isn't my mother tongue and googeling the prob also doesn't help.

    Could anyone please explain me the error above or give me a hint
    what im doing wrong?

    Thx for reading/helping

    kox

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