Subversion Repositories openrisc_2011-10-31

/*

 * 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]>,

                       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 */