{{keywords>wiki library source code example reference}}
===== fflush =====

<code c>
    int fflush(FILE *stream);
</code>

Flushes stream stream and returns zero on success or EOF on error. Effect undefined for input stream. fflush(NULL) flushes all output streams.

===== C Sourcecode Example =====
<code c>
/* 
 * fflush example code
 * http://code-reference.com/c/stdio.h/fflush 
 */

#include <stdio.h> /* including standard library */
//#include <windows.h> /* uncomment this for Windows */

#define MAX 80
int main( void )
{
  FILE *filestream = fopen("test.txt", "rt+");
  char buffer[MAX];
  if (filestream)
  {
    fputs("write this in a file", filestream);
    fflush(filestream); /* uncomment this function to see what's happend */
    fgets(buffer, MAX, filestream);
    puts(buffer);
    fclose(filestream);
  }
  return 0;
}
</code>

=== test.txt ===
file test.txt
<code c>
Line 1
#Line2
Line 3
#Line 4 
Line 
</code>

==== fflush output ====
    output: ./fflush

test.txt after running the programm    
<code c>
write this in a file
#Line 4 
Line 5
</code>