ferror与feof

#include<stdio.h>
#include<stdlib.h>
int find_int(const char*);
int main()
{
printf("%d",find_int("test.bin"));
return 0;
}


int find_int(const char *filename)
{
FILE *fp=fopen(filename,"r");
int n;


if(fp==NULL)
return -1;


while(fscanf(fp,"%e",&n)!=1)
{
if(ferror(fp))
{
fclose(fp);
return -2;
}


if(feof(fp))
{
fclose(fp);
return -3;
}
fscanf(fp,"%*[^\n]"); //跳过全部字符直到下一个换行符为止的用法
}


fclose(fp);
return n;
}