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/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
FUNCTION
<<fsetpos>>---restore position of a stream or file
INDEX
fsetpos
INDEX
_fsetpos_r
ANSI_SYNOPSIS
#include <stdio.h>
int fsetpos(FILE *<[fp]>, const fpos_t *<[pos]>);
int _fsetpos_r(struct _reent *<[ptr]>, FILE *<[fp]>, l
const fpos_t *<[pos]>);
TRAD_SYNOPSIS
#include <stdio.h>
int fsetpos(<[fp]>, <[pos]>)
FILE *<[fp]>;
fpos_t *<[pos]>;
int _fsetpos_r(<[ptr]>, <[fp]>, <[pos]>)
struct _reent *<[ptr]>;
FILE *<[fp]>;
fpos_t *<[pos]>;
DESCRIPTION
Objects of type <<FILE>> can have a ``position'' that records how much
of the file your program has already read. Many of the <<stdio>> functions
depend on this position, and many change it as a side effect.
You can use <<fsetpos>> to return the file identified by <[fp]> to a previous
position <<*<[pos]>>> (after first recording it with <<fgetpos>>).
See <<fseek>> for a similar facility.
RETURNS
<<fgetpos>> returns <<0>> when successful. If <<fgetpos>> fails, the
result is <<1>>. The reason for failure is indicated in <<errno>>:
either <<ESPIPE>> (the stream identified by <[fp]> doesn't support
repositioning) or <<EINVAL>> (invalid file position).
PORTABILITY
ANSI C requires <<fsetpos>>, but does not specify the nature of
<<*<[pos]>>> beyond identifying it as written by <<fgetpos>>.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
int
_DEFUN(_fsetpos_r, (ptr, iop, pos),
struct _reent * ptr _AND
FILE * iop _AND
_CONST _fpos_t * pos)
{
int x = _fseek_r (ptr, iop, *pos, SEEK_SET);
if (x != 0)
return 1;
return 0;
}
#ifndef _REENT_ONLY
int
_DEFUN(fsetpos, (iop, pos),
FILE * iop _AND
_CONST _fpos_t * pos)
{
return _fsetpos_r (_REENT, iop, pos);
}
#endif /* !_REENT_ONLY */
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