尝试从 C 中的 txt 文件中读取数字时出错

Question

I am new to C programming and I am getting a THREAD 1: EXC_BAD_ACCESS(code = 1, address 0x68) when I run my program. The purpose of my code is to read from a txt file that contains positive and negative numbers and do something with it.

#include <stdio.h>

int main (int argc, const char * argv[]) {

    FILE *file = fopen("data.txt", "r");
    int array[100];

    int i = 0;
    int num;

    while( fscanf(file, "%d" , &num) == 1) { // I RECEIVE THE ERROR HERE
        array[i] = num;
        printf("%d", array[i]);
        i++;
    }
    fclose(file);

    for(int j = 0; j < sizeof(array); j++){
        printf("%d", array[j]);
    }
}

Answer 1

After

FILE *file = fopen("data.txt", "r");

Say

if(file == 0) {
    perror("fopen");
    exit(1);
}

Just a guess, the rest of the code looks ok, so likely this is the problem.

Answer 2

Also worth noting that you might have more than 100 numbers in your file, in which case you will blow past the size of your array. Try replacing the while loop with this code:

for (int i = 0; i < 100 && ( fscanf(file, "%d" , &num) == 1); ++i)
{
    array[i] = num;
    printf("%d", array[i]);
}

Answer 3

Do you have the file "data.txt" created and local?

touch data.txt
echo 111 222 333 444 555 > data.txt

Check that your file open succeeded.

Here is a working version,

#include <stdio.h>
#include <stdlib.h> //for exit
int main (int argc, const char * argv[])
{
    FILE *fh; //reminder that you have a file handle, not a file name
    if( ! (fh= fopen("data.txt", "r") ) )
    {
       printf("open %s failed\n", "data.txt"); exit(1);
    }

    int array[100];
    int idx = 0; //never use 'i', too hard to find
    int num;
    while( fscanf(fh, "%d" , &num) == 1) { // I RECEIVE THE ERROR HERE
        array[idx] = num;
        printf("%d,", array[idx]);
        idx++;
    }
    printf("\n");
    fclose(fh);

    //you only have idx numbers (0..idx-1)
    int jdx;
    for(jdx = 0; jdx<idx; jdx++)
    {
        printf("%d,", array[jdx]);
    }
    printf("\n");
}