# 标准库stdio.h函数fflush()

**原型**

```c
int fflush(FILE * stream);
```

**说明**

主要用来刷新流。

**参数**

```
stream: 一个指向FILE类型的指针
```

**返回值**

如果成功则返回 0 值；如果失败或者发生错误，会输出错误流，直到EOF标志位。

**实例**

```c
/* fflush example */
#include <stdio.h>
char mybuffer[80];
int main()
{
   FILE * pFile;
   pFile = fopen ("example.txt","r+");
   if (pFile == NULL) perror ("Error opening file");
   else {
     fputs ("test",pFile);
     fflush (pFile);    // flushing or repositioning required
     fgets (mybuffer,80,pFile);
     puts (mybuffer);
     fclose (pFile);
     return 0;
  }
}
```


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