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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,
* and/or 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
<<fseek>>, <<fseeko>>---set file position
INDEX
fseek
INDEX
fseeko
INDEX
_fseek_r
INDEX
_fseeko_r
SYNOPSIS
#include <stdio.h>
int fseek(FILE *<[fp]>, long <[offset]>, int <[whence]>);
int fseeko(FILE *<[fp]>, off_t <[offset]>, int <[whence]>);
int _fseek_r(struct _reent *<[ptr]>, FILE *<[fp]>,
long <[offset]>, int <[whence]>);
int _fseeko_r(struct _reent *<[ptr]>, FILE *<[fp]>,
off_t <[offset]>, int <[whence]>);
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 <<fseek>>/<<fseeko>> to set the position for the file identified by
<[fp]>. The value of <[offset]> determines the new position, in one
of three ways selected by the value of <[whence]> (defined as macros
in `<<stdio.h>>'):
<<SEEK_SET>>---<[offset]> is the absolute file position (an offset
from the beginning of the file) desired. <[offset]> must be positive.
<<SEEK_CUR>>---<[offset]> is relative to the current file position.
<[offset]> can meaningfully be either positive or negative.
<<SEEK_END>>---<[offset]> is relative to the current end of file.
<[offset]> can meaningfully be either positive (to increase the size
of the file) or negative.
See <<ftell>>/<<ftello>> to determine the current file position.
RETURNS
<<fseek>>/<<fseeko>> return <<0>> when successful. On failure, the
result is <<EOF>>. 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 <<fseek>>.
<<fseeko>> is defined by the Single Unix specification.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
#include <errno.h>
#include "local.h"
int
_fseek_r (struct _reent *ptr,
register FILE *fp,
long offset,
int whence)
{
return _fseeko_r (ptr, fp, offset, whence);
}
#ifndef _REENT_ONLY
int
fseek (register FILE *fp,
long offset,
int whence)
{
return _fseek_r (_REENT, fp, offset, whence);
}
#endif /* !_REENT_ONLY */
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