newlib/libc/stdio/rewind.c

   1 /*
   2  * Copyright (c) 1990 The Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms are permitted
   6  * provided that the above copyright notice and this paragraph are
   7  * duplicated in all such forms and that any documentation,
   8  * and/or other materials related to such
   9  * distribution and use acknowledge that the software was developed
  10  * by the University of California, Berkeley.  The name of the
  11  * University may not be used to endorse or promote products derived
  12  * from this software without specific prior written permission.
  13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  16  */
  17
  18 /*
  19 FUNCTION
  20 <<rewind>>---reinitialize a file or stream
  21
  22 INDEX
  23         rewind
  24 INDEX
  25         _rewind_r
  26
  27 SYNOPSIS
  28         #include <stdio.h>
  29         void rewind(FILE *<[fp]>);
  30         void _rewind_r(struct _reent *<[ptr]>, FILE *<[fp]>);
  31
  32 DESCRIPTION
  33 <<rewind>> returns the file position indicator (if any) for the file
  34 or stream identified by <[fp]> to the beginning of the file.  It also
  35 clears any error indicator and flushes any pending output.
  36
  37 RETURNS
  38 <<rewind>> does not return a result.
  39
  40 PORTABILITY
  41 ANSI C requires <<rewind>>.
  42
  43 No supporting OS subroutines are required.
  44 */
  45
  46 #if defined(LIBC_SCCS) && !defined(lint)
  47 static char sccsid[] = "%W% (Berkeley) %G%";
  48 #endif /* LIBC_SCCS and not lint */
  49
  50 #include <_ansi.h>
  51 #include <reent.h>
  52 #include <stdio.h>
  53
  54 void
  55 _rewind_r (struct _reent * ptr,
  56        register FILE * fp)
  57 {
  58   (void) _fseek_r (ptr, fp, 0L, SEEK_SET);
  59   clearerr (fp);
  60 }
  61
  62 #ifndef _REENT_ONLY
  63
  64 void
  65 rewind (register FILE * fp)
  66 {
  67   _rewind_r (_REENT, fp);
  68 }
  69
  70 #endif /* !_REENT_ONLY */