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I am trying to learn C. I want to fill a 2D array from a 1D array that I have got from a File.

Now, I am trying to take the elements of array pointer that outputs (Hello,My,name,is,Ram.) into a 2D array called words. the purpose is to remove commas and highlight each word in a different row. I have achieved that too However I am getting some gibberish along with my output. I have checked my entries one by one and found that the first line(Hello,My,name,is,Ram.) is stored in from row 1 to 5 in words[][]. the values contained in words[][] between row 5 to 10 is gibberish. However, the next line(I,own,20,thousand,bucks.) starts at row [10] of word that I don't understand why? plus my output looks weird with some unknown values. Please inform me what should I do to correct my output and size the 2 D array equal to the value it contains

Here's my code:
int main(int argc, const char * argv[]) {
    // insert code here...
    FILE *fp;
    char (*points)[50];
    char *array;
    int width=20,height=50;
    char *word;
    char words [width][height];
    int counter=0; // To traverse through array and tracks the current position in array.
    points = malloc(sizeof(*points) * 2);

    word=malloc(width*height*sizeof(char));
    if (points == NULL) {
        perror("malloc");
        exit(0);
    }
    fp = fopen("/Users/shubhamsharma/Desktop/data.txt", "r");
    if (fp == NULL) {
        perror("fopen");
        exit(EXIT_FAILURE);
    }
    fgets(points[0], sizeof(*points), fp);
    fgets(points[1], sizeof(*points), fp);
    array=points[0];
    printf("%s", points[0]);
    printf("%s", points[1]);

    for(int i=0;i<width;i++)
    {
        for(int j=0,p=counter;j<height;j++,p++)
        {
            if(array[p]==','||array[p]=='\0')
            {
                words[i][j]='\n';
                counter=++p;
                break;
            }
            else
                words[i][j]=array[p];

        }}

    printf("\n%c",words[16][0]);
    for (int i=0; i<width; i++) {
        for (int j=0; j<height; j++) {

            if(words[i][j]=='\n')
            {
                break;
            }
            printf("\nPrinting element in word\n");
            printf("%c",words[i][j]);

        }
    }

    printf("\n");
    fclose(fp);

    free(points);
    return 0;
    return 0;
    }


Output:

Hello,My,name,is,Ram. I,own,20,thousand,bucks. Printing element in word
HelloMynameisRam.+̮\213\377\310`\267t\377̮\213\377Iown20thousandbucks.
Program ended with exit code: 0

Lines in my file looks something like.-

Hello,My,name,is,Ram.
I,own,20,thousand,bucks.
Posted
Comments
[no name] 24-Jan-23 5:01am    
I don't see how the code provided ever compiled much less ran without segfault before any output.

char (*points)[50] is an array of 50 8 byte ptrs to char.

malloc sizeof(*points) * 2, which is 16 bytes because *points is an address.

No cast of void ptr from malloc but malloc tries to do the right thing and gives an address to a 400 byte block of memory for 50 ptrs, 8 bytes each.

Allocate memory for 'word', 1000 bytes, and never use it.

Use fgets to read sizeof(*points) which is 8 bytes, so fgets reads 7 bytes
and adds a null byte back into points[0] which is a ligit address.

Next fgets reads 8 more bytes and trys to put it in points[1] but points[1] is not an address to the malloc'd memory and segfault occurs.

lots is wrong but whats the point?

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