genericopenlibs/cstdlib/LSTDIO/FSETPOS.C
author Shabe Razvi <shaber@symbian.org>
Thu, 02 Sep 2010 17:14:31 +0100
branchRCL_3
changeset 58 104bd6aeae10
parent 0 e4d67989cc36
permissions -rw-r--r--
Merge RCL_3 fixes with reverted delivery

/*
* Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description:
* FUNCTION
* <<fsetpos>>---restore position of a stream or file
* INDEX
* fsetpos
* ANSI_SYNOPSIS
* #include <stdio.h>
* int fsetpos(FILE *<[fp]>, const fpos_t *<[pos]>);
* TRAD_SYNOPSIS
* #include <stdio.h>
* int fsetpos(<[fp]>, <[pos]>)
* FILE *<[fp]>;
* fpos_t *<[pos]>;
* 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 <stdio.h>

/**
Reposition file pointer to a saved location.
@return   If successful the function returns 0.
Otherwise it returns nonzero and sets the global variable errno to a non-zero value.
@param iop Pointer to an open file.
@param pos Position value obtained from a previous call to fgetpos that indicates 
the position of the file pointer at that moment.
*/
EXPORT_C int
fsetpos (FILE * iop, const fpos_t * pos)
{
  int x = fseek (iop, *pos, SEEK_SET);

  if (x != 0)
    return 1;
  return 0;
}