Thread: union will support dynamic memory allocation?

  1. #1
    kotin
    Join Date
    Oct 2009
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    132

    union will support dynamic memory allocation?

    Hi All,

    recently i studied one document for difference between structure and union. I that they said, union did not support the dynamic memory allocation and structure should support dynamic memory allocation.

    I tried one program with dynamic memory allocation as below

    Code:
    #include<stdio.h>
    #include<stdlib.h>
    #include<malloc.h>
    union koti
    {
        int i;
        float f;
        char c;
    };
    int main()
    {
        union koti  *p;
        p= (union  koti *)malloc(1 * sizeof(union koti));
        p->f =12.3;
        printf ("%f\n",p->f);
        return 0;
    }
    Am i correct? above program can prove that union will support dynamic memory allocation?

    Please correct me if i am wrong.

    Thanks in advance.

  2. #2
    Banned
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    Easy way to find out... compile it and test it.

  3. #3
    kotin
    Join Date
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    HI ya, i compiled and i am getting the output as 12.300000.

  4. #4
    kotin
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    i Got the my first thread statement from below URL

    C question : Difference between structure and union.

    I am not sure as it is correct point or wrong point above URL "4. memory can be allocated dynamically in structures,where as in union can not be alloacted dynamically."

    please let me know.

    Thnaks in advance.

  5. #5
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    Of course a union can be allocated dynamically... any variable type can.

  6. #6
    kotin
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    Means, the point what i read for unions as"memory can be allocated dynamically in structures,where as in union can not be alloacted dynamically" is wrong? from the URL C question : Difference between structure and union.

    I think some one posted wrong point? am i right?

  7. #7
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    You've tested it yourself. You have confirmation... what more do you need?

  8. #8
    kotin
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    Thanks for your reply's.

  9. #9
    'Allo, 'Allo, Allo
    Join Date
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    You know that guys response is slighty dodgy when his point numbering contains two 4's, provides 7 points when he says there are 6 differences, he fails to spell union correctly and his simple demos wouldn't compile. Not to mention it's an Indian C programming site, which should make you immediately doubt the veracity of its contents.

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