Am I doing something wrong in my file-reader function? - c

Question

I'm a beginner to C and wanted to code a simple function that reads the content of file and returns it as a string, as an exercise.
Here is my solution which I think works, but is there any obvious bad practices or unoptimal code here ? For example, I manually added a \0 at the end of the string, but I don't know if it is really necessary...
#include <stdio.h>
#include <stdlib.h>
char *readFile(char *path)
{
//open file
FILE *file = fopen(path, "r");
//if broken
if (file == NULL)
{
printf("Erreur");
return NULL;
}
//return variable
char *result;
//length of the file
int len;
fseek(file, 0, SEEK_END);
len = ftell(file);
fseek(file, 0, SEEK_SET);
//initialising return variable
result = (char*) malloc(sizeof(char) * (len + 1));
int c;
int i = 0;
while (feof(file) == 0)
{
c = fgetc(file);
if (c != EOF)
{
printf("%04x -> %c\n", c, c);
*(result + i) = c;
i++;
}
}
*(result + i) = '\0';
printf("len : %i\n", len);
fclose(file);
return result;
}

Answer 1

I'd replace this:
int c;
int i = 0;
while (feof(file) == 0)
{
c = fgetc(file);
if (c != EOF)
{
printf("%04x -> %c\n", c, c);
*(result + i) = c;
i++;
}
}
with this:
fread(file, 1, len, result);
It's much shorter
It's correct
It's certainly faster
There is still room for improvement though, for example you could add error handling, fread can fail.

Answer 2

Since you have already got the length of the file to be read, you could also read them at once instead char-by-char.
Another implmentation of your function, for example:
char *readFile(char *path)
{
//open file
FILE *file = fopen(path, "r");
//if broken
if (file == NULL)
{
printf("Erreur");
return NULL;
}
//return variable
char *result;
//length of the file
int len;
fseek(file, 0, SEEK_END);
len = ftell(file);
fseek(file, 0, SEEK_SET);
//initialising return variable
result = (char*) malloc(sizeof(char) * (len + 1));
size_t i = fread(result, sizeof(char), len, file);
*(result + i) = '\0';
printf("len : %i\n", len);
fclose(file);
return result;
}