Rewind

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Description

Set position of stream to the beginning.

Sets the position indicator associated with stream to the beginning of the file.

The end-of-file and error internal indicators associated to the stream are cleared after a successful call to this function, and all effects from previous calls to
ungetc
on this stream are dropped.

On streams open for update (read+write), a call to rewind allows to switch between reading and writing.

Syntax

void rewind ( FILE * stream );

Parameters

stream
Pointer to a object that identifies the stream.

Return Value

none

Example

#include <stdio.h>

int main ()
{
  int n;
  FILE * pFile;
  char buffer [27];

  pFile = fopen ("myfile.txt","w+");
  for ( n='A' ; n<='Z' ; n++)
    fputc ( n, pFile);
  rewind (pFile);
  fread (buffer,1,26,pFile);
  fclose (pFile);
  buffer[26]='\0';
  puts (buffer);
  return 0;
}
A file called
myfile.txt
is created for reading and writing and filled with the alphabet. The file is then rewinded, read and its content is stored in a buffer, that then is written to the standard output:
ABCDEFGHIJKLMNOPQRSTUVWXYZ