pointer to array of arrays

This is a discussion on pointer to array of arrays within the C Programming forums, part of the General Programming Boards category; I wrote this code and have a pointer that I want to point to another character array of arrays. But ...

  1. #1
    Registered User linuxdude's Avatar
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    pointer to array of arrays

    I wrote this code and have a pointer that I want to point to another character array of arrays. But it says
    Code:
    :24: error: incompatible types in assignment
    here is my code
    Code:
    #include <stdio.h>
    #define SIZE 3
    
    char array[SIZE+4][SIZE+2];
    char *view[SIZE+4];
    
    void input(void){
            int x;
            for(x=0;x<SIZE;x++){
                    fgets(&array[x][2],sizeof(array[x]),stdin);
            };
    }
    
    void print(void){
            int x;
            for(x=0;x<SIZE;x++){
                    printf("%s\n",array[x]);
            }
    }
    
    int main(void){
            int x,y;
            input();
            view=array;
            for(y=0;y<SIZE+2;y++){
                    array[SIZE+3][y]='\0';
                    array[0][y]='\0';
            }
            for(x=0;x<SIZE+4;x++){
                    array[x][0]='\0';
                    array[x][SIZE+1]='\0';
            }
            for(x=1;x<SIZE+1;y++){
                    view[x][1]=array[x][SIZE+1];
                    view[x][SIZE+2]=array[x][1];
            }
            print();
            return 0;
    }

  2. #2
    and the hat of int overfl Salem's Avatar
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    > view=array;
    If you want to do this

    Then you need this
    char (*view)[SIZE+4];

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  3. #3
    Registered User linuxdude's Avatar
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    ah yes,
    Code:
    char (*view)[SIZE+4];
    is a pointer to a character array of SIZE+4 rows, and
    Code:
     char *view[SIZE+4];
    creates a single array of SIZE+4 pointers to characters?
    Also. I changed the code to
    Code:
    char (*view)[SIZE+4]
    and I get the same error? What am i doing wrong?

  4. #4
    and the hat of int overfl Salem's Avatar
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    Sorry, got the wrong dimension in there, it should be +2, not +4

    Code:
    void foo ( ) {
        char a[10][20];
        char (*pa)[10][20];
        char (*pb)[20];
        char *pc;
        pa = &a;
        pb = &a[0];     /* pb = a; also works */
        pc = &a[0][0];
    }
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

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