Typo on C-FAQ

This is a discussion on Typo on C-FAQ within the General Discussions forums, part of the Community Boards category; From the chapter "A tutorial on Pointer" i see the following snippet of code Code: const int cintA = 10; ...

  1. #1
    Registered User ssharish2005's Avatar
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    Typo on C-FAQ

    From the chapter "A tutorial on Pointer" i see the following snippet of code

    Code:
    const int cintA = 10;                     // A constant int
    int       intB = 20;                      // A nonconstant int
    const int *pointer_to_const_int = &cintA; // A pointer to a const int. The POINTER ITSELF IS NOT CONST.
    *pointer_to_const_int = 20;               // Compiler error *pointer_to_const_int is a constant 
                                              // and cannot be changed.
    pointer_to_const_int++;                   // This is fine, it's simple pointer arithmetic 
                                              // moving the pointer to the next memory location.  
                                              // The pointer itself is not const so it may be repointed.
    const int *const  const_pointer_to_const_int = &cintA;  // Here we have a constant pointer to a 
                                              // constant int. Notice as pointer is const we must 
                                              // initialise it here.
    const_pointer_to_const_int++;             // This is now illegal. The pointer itself is const 
                                              // and may not be repointed.
    *const_pointer_to_const_int = 40;         // Again compiler error. Pointer points to constant data. 
                                              // You cannot write through this pointer.
    int *pointer_to_int = *intB;
    *pointer_to_int = 40;                     // This is fine. Data pointed to is not constant.
    pointer_to_int++;                         // Again fine, pointer is not constant, you may repoint it.
    int *const  const_pointer_to_int = &intB; // Constant pointer to non-constant int. 
                                              // Pointer is const so must be initialised here.
    const_pointer_to_int++;                   // Compiler error. The pointer itself is constant and 
                                              // may not be repointed.
    *const_pointer_to_int = 80;               // This is fine. Although the pointer is constant the object
                                              // pointed to is not constant and so may be written to.
    Highlighted statment - Shouldn't that be?

    Code:
    int *pointer_to_int = &intB;
    ssharish
    Life is like riding a bicycle. To keep your balance you must keep moving - Einstein

  2. #2
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    Yes, I think you're correct. Trying to compile the relevant lines results in "error: invalid type argument of ‘unary *’ (have ‘int’)" on my system.

  3. #3
    Registered User ssharish2005's Avatar
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    Yes this needs to be changed. Calling administrators *shout loud*

    ssharish
    Life is like riding a bicycle. To keep your balance you must keep moving - Einstein

  4. #4
    Administrator webmaster's Avatar
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    Thank you for the report; I have corrected this typo.

    By the way, the fastest way to report errors is to email me directly at webmaster@cprogramming.com.

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