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/*
* lseek() - POSIX 1003.1b 6.5.3 - Reposition Read/Write File Offset
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
* Copyright assigned to U.S. Government, 1994.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#include <stdio.h>
#include "libio_.h"
off_t lseek(
int fd,
off_t offset,
int whence
)
{
rtems_libio_t *iop;
rtems_libio_check_fd( fd );
iop = rtems_libio_iop( fd );
rtems_libio_check_is_open(iop);
/*
* Now process the lseek().
*/
switch ( whence ) {
case SEEK_SET:
iop->offset = offset;
break;
case SEEK_CUR:
iop->offset += offset;
break;
case SEEK_END:
iop->offset = iop->size - offset;
break;
default:
errno = EINVAL;
return -1;
}
if ( !iop->handlers->lseek )
set_errno_and_return_minus_one( ENOTSUP );
return (*iop->handlers->lseek)( iop, offset, whence );
}
/*
* _lseek_r
*
* This is the Newlib dependent reentrant version of lseek().
*/
#if defined(RTEMS_NEWLIB)
#include <reent.h>
off_t _lseek_r(
struct _reent *ptr,
int fd,
off_t offset,
int whence
)
{
return lseek( fd, offset, whence );
}
#endif
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