difference between: const char *, char *

This is a discussion on difference between: const char *, char * within the C Programming forums, part of the General Programming Boards category; Can anyone tell me the difference (if any) of the following (memory wise) of using const * vs char *: ...

  1. #1
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    difference between: const char *, char *

    Can anyone tell me the difference (if any) of the following (memory wise) of using const * vs char *:

    Code:
    #include <conio.h>
    #include <stdio.h>
    
    #define GET_NUM_ELEMENTS(x) (sizeof(x) / sizeof(x[0]))
    
    int main(void)
    {
        const char *cStr = "Stuff";
        char *str = "Stuff";
    
        const char *cStrArray[] = { "Um", "Some", "Words" };
        char *strArray[] = { "Um", "Some", "Words" };
    
        for(register unsigned int i = 0; i < GET_NUM_ELEMENTS(StrArray); i++)
            printf("%s ", strArray[i]);
    
        getch();
    
        return 0;
    }
    Thanks.

  2. #2
    Obsessed with C chrismiceli's Avatar
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    const char * make the char pointed at contant, but char * makes it constant.

  3. #3
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    Hi,
    I think memory wise no difference. Only this difference:
    char *p="name";
    p="newname";//possible
    *p='q';//possible
    But,
    const char *p="name";
    p="newname";//possible
    *p='q';//not possible.
    Saravanan.T.S.
    Beginner.

  4. #4
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    Thanks for the fast reply.
    Not sure what chrismiceli is getting at though.

    saravanan_ts: im assuming the memory is automatically resized when:

    Code:
    p="newname"; //possible
    *p='q';	     //possible
    and there is no need for a malloc(), free() call??

    also re you sure this is possible:
    Code:
    const char *p="name";
    p = "newname"; //possible
    just thinking the compiler aint going to like changing a const

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