fgets()问题？

DIDNOT

我再读取一个文件的时候，为什么最后一句会输出两次？
如下
FILE *nn;
char buffer[256];



while(!feof(nn)){fgets(buffer,256,nn);puts(bufffer);}

yalefield

很多地方对feof的解释是错误的。有些解释是对的，但例子是错误的。
feof只是对已经读过的内容来判断文件是否结束，因此，
while(！feof(nn)){...}这种用法实际上是错误的！
您还没有读，怎么判断文件是否结束？
正确的用法是：

while (1)
{
   fgets(...);
   if (feof(nn))
   {
      break;
   }
   puts(...);
}

DIDNOT

太谢谢了

pengjiajun

正对feof()疑惑...感谢...

jiajs

Tests whether the file position is at the end

#include <stdio.h>
int feof ( FILE *fp  );



The feof( ) macro tests whether the file position indicator of a given file is at the end of the file.

The feof( ) macro's argument is a FILE pointer. One attribute of the file or stream referenced by this pointer is the end-of-file flag, which indicates that the program has attempted to read past the end of the file. The feof( ) macro tests the end-of-file flag and returns a nonzero value if the flag is set. If not, feof( ) returns 0.