Array and file I/O-CodePudding

I have following data in a file:

Name 
Surname

#include <stdio.h>
#define FILENAME "file.txt"
#define MAXSIZE 128
int main(void)
{
    setvbuf(stdout, NULL, _IONBF, 0);
    FILE *file = fopen(FILENAME, "r");

    if (!file) {
        perror(FILENAME);
        return 1;
    }

    int ch;
    size_t i = 0;
    char array[3][MAXSIZE];
    for(int a=0; a < 3; a  )
    {
        while (i < MAXSIZE - 1 && ((ch = getc(file)) != EOF))
        {
            if (ch == '\n')
                break;
            
            array[a][i  ] = ch;
        }
    /* null-terminate the array to create a string */
        array[a][i] = '\0';
    }
    fclose(file);
    for(int a=0; a < 3; a  )
    {
        for(int i=0; i < 10; i  )
        {
            printf("%c", array[a][i]);
        }
    }
}

When I run this program it gives me output like this "

How can I modify it, so it will not output garbage? This is a link to my previous post: Link

CodePudding user response：

As I noted in a comment:

Your printing loop for (int i=0; i < 10; i ) { printf("%c", array[a][i]); } needs to stop when array[a][i] == '\0' —— add if (array[a][i] == '\0') break; before the printf().

You also need to reset i to 0 before the while loop (but after the for loop). If you declared i inside the first for loop, you'd not have the problems you do.

Note that you have two different variables called i (one is size_t i = 0; before the loops; the other is for (int i = 0; …) while printing) and one hides the other. That can lead to confusion.

Those changes might lead to this code:

#include <stdio.h>

#define FILENAME "file.txt"
#define MAXSIZE 128

int main(void)
{
    setvbuf(stdout, NULL, _IONBF, 0);
    FILE *file = fopen(FILENAME, "r");

    if (!file) {
        perror(FILENAME);
        return 1;
    }

    char array[3][MAXSIZE];
    for (int a = 0; a < 3; a  )
    {
        int ch;
        size_t i = 0;
        while (i < MAXSIZE - 1 && ((ch = getc(file)) != EOF))
        {
            if (ch == '\n')
                break;            
            array[a][i  ] = ch;
        }
        array[a][i] = '\0';
    }
    fclose(file);
    for (int a = 0; a < 3; a  )
    {
        for (int i = 0; i < 10; i  )
        {
            if (array[a][i] == '\0')
                break;
            printf("%c", array[a][i]);
        }
    }
}

There's also no obvious reason not to print the data using:

for (int a = 0; a < 3; a  )
    puts(array[a]);

for (int a = 0; a < 3; a  )
    printf("%s\n", array[a]);