Thread: Const qualifier

  1. #1
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    Const qualifier

    From the definition of const qualifier, that the variable value cannot be changed in the current file, but can be changed in another file, I tried to write the program but resulted in segmentation fault.

    file1.c
    Code:
    #include<stdio.h>
    const int x = 5;
    void main(){
          printf("%d",x);  
          show();
    }
    file2.c
    Code:
    void show()
    {
         extern int x;
         x++;
         printf("%d",x);
    }
    Please help me..

  2. #2
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  3. #3
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    Please tell me what is wrong in this....

  4. #4
    Algorithm Dissector iMalc's Avatar
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    The variable is declared as const. It's not allowed to modify it under any circumstance.

    Perhaps you're trying to come up with an example where a value is allowed to be modified in one function but is read-only in another?
    For that you could have a non-const global variable, and one function that just happily assigns to it, and another that takes a pointer to const which is passed the address of variable.
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