fopen读写文件

#include <stdio.h>  
#include <stdlib.h>  
  
void write_file(FILE *fp, unsigned char *arr, int len)  
{  
    int i = 0;
    for(i = 0 ; i < len; i+=2)  
    {     
        fprintf(fp,"0x%x,\n", arr[i]);  
    }  
} 
void read_file(FILE *fp, unsigned char* arr, int len)
{
	int i = 0;
	for (i = 0; i < len; i++)
	{
		fscanf(fp, "%c", arr+i);
	}
	
} 
  
int main(void)  
{  
    FILE *fp1, *fp2;  
    unsigned char *arr;
    arr = (unsigned char *)malloc(4096);
    fp1=fopen("test.txt", "rb");
    fp2=fopen("out.txt","a+"); 
    read_file(fp1, arr, 4096);
    write_file(fp2, arr, 4096);  
    fclose(fp1);  
    fclose(fp2);
    free(arr);  
    return 0;
}