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/* 
   Copyright (C) 1994, 1995 Free Software Foundation

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */

#include "priv.h"
#include "io_S.h"
#include <unistd.h>

#define diskfs_readonly 0
#define diskfs_synchronous 0

/* Implement io_seek as described in <hurd/io.defs>. */
kern_return_t
diskfs_S_io_seek (struct protid *cred,
		  off_t offset,
		  int whence,
		  off_t *newoffset)
{
  
  CHANGE_NODE_FIELD (cred,
		   ({
		     ioserver_get_conch (&np->conch);
		     switch (whence)
		       {
		       case SEEK_SET:
			 err = 0;
			 cred->po->filepointer = offset;
			 break;
		       case SEEK_CUR:
			 err = 0;
			 cred->po->filepointer += offset;
			 break;
		       case SEEK_END:
			 err = 0;
			 cred->po->filepointer = (np->dn_stat.st_size
						  + offset);
			 break;
		       default:
			 err = EINVAL;
			 break;
		       }
		     *newoffset = cred->po->filepointer;
		   }));
}