rewind (CRT)

Run-Time Library Reference

rewind

Repositions the file pointer to the beginning of a file.

void rewind(
   FILE *stream 
);

Parameters

stream: Pointer to FILE structure.

Remarks

The rewind function repositions the file pointer associated with stream to the beginning of the file. A call to rewind is similar to

(void) fseek( stream, 0L, SEEK_SET );

However, unlike fseek, rewind clears the error indicators for the stream as well as the end-of-file indicator. Also, unlike fseek, rewind does not return a value to indicate whether the pointer was successfully moved.

To clear the keyboard buffer, use rewind with the stream stdin, which is associated with the keyboard by default.

If stream is a NULL pointer, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, this function returns and errno is set to EINVAL.

For information on these and other error codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.

Requirements

Routine	Required header	Compatibility
rewind	<stdio.h>	ANSI, Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003

For additional compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

Example

// crt_rewind.c
/* This program first opens a file named
 * crt_rewind.out for input and output and writes two
 * integers to the file. Next, it uses rewind to
 * reposition the file pointer to the beginning of
 * the file and reads the data back in.
 */
#include <stdio.h>

int main( void )
{
   FILE *stream;
   int data1, data2;

   data1 = 1;
   data2 = -37;

   fopen_s( &stream, "crt_rewind.out", "w+" );
   if( stream != NULL )
   {
      fprintf( stream, "%d %d", data1, data2 );
      printf( "The values written are: %d and %d\n", data1, data2 );
      rewind( stream );
      fscanf_s( stream, "%d %d", &data1, &data2 );
      printf( "The values read are: %d and %d\n", data1, data2 );
      fclose( stream );
   }
}

Output

The values written are: 1 and -37
The values read are: 1 and -37

.NET Framework Equivalent

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

Reference

Stream I/O