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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
<<fgetpos>>---record position in a stream or file
INDEX
fgetpos
INDEX
_fgetpos_r
SYNOPSIS
#include <stdio.h>
int fgetpos(FILE *restrict <[fp]>, fpos_t *restrict <[pos]>);
int _fgetpos_r(struct _reent *<[ptr]>, FILE *restrict <[fp]>, fpos_t *restrict <[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 <<fgetpos>> to report on the current position for a file
identified by <[fp]>; <<fgetpos>> will write a value
representing that position at <<*<[pos]>>>. Later, you can
use this value with <<fsetpos>> to return the file to this
position.
In the current implementation, <<fgetpos>> simply uses a character
count to represent the file position; this is the same number that
would be returned by <<ftell>>.
RETURNS
<<fgetpos>> returns <<0>> when successful. If <<fgetpos>> fails, the
result is <<1>>. Failure occurs on streams that do not support
positioning; the global <<errno>> indicates this condition with the
value <<ESPIPE>>.
PORTABILITY
<<fgetpos>> is required by the ANSI C standard, but the meaning of the
value it records is not specified beyond requiring that it be
acceptable as an argument to <<fsetpos>>. In particular, other
conforming C implementations may return a different result from
<<ftell>> than what <<fgetpos>> writes at <<*<[pos]>>>.
No supporting OS subroutines are required.
*/
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
int
_DEFUN(_fgetpos_r, (ptr, fp, pos),
struct _reent * ptr _AND
FILE *__restrict fp _AND
_fpos_t *__restrict pos)
{
*pos = _ftell_r (ptr, fp);
if (*pos != -1)
{
return 0;
}
return 1;
}
#ifndef _REENT_ONLY
int
_DEFUN(fgetpos, (fp, pos),
FILE *__restrict fp _AND
_fpos_t *__restrict pos)
{
return _fgetpos_r (_REENT, fp, pos);
}
#endif /* !_REENT_ONLY */
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