/* Implementation of the FLUSH intrinsic.
   Copyright (C) 2004 Free Software Foundation, Inc.
   Contributed by Steven G. Kargl <kargls@comcast.net>.

This file is part of the GNU Fortran 95 runtime library (libgfortran).

Libgfortran is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

Libgfortran 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with libgfor; see the file COPYING.LIB.  If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


#include "config.h"
#include "libgfortran.h"

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif

#include "../io/io.h"

/* SUBROUTINE FLUSH(UNIT)
   INTEGER, INTENT(IN), OPTIONAL :: UNIT  */

static void
recursive_flush (gfc_unit *us)
{
  /* There can be no open files.  */
  if (us == NULL)
    return;

  flush (us->s);
  recursive_flush (us->left);
  recursive_flush (us->right);
}


void
prefix(flush_i4) (GFC_INTEGER_4 * unit)
{

  gfc_unit *us;

  /* flush all streams */
  if (unit == NULL)
    {
      us = g.unit_root;
      recursive_flush(us);
    }
  else
    {
      us = find_unit(*unit);
      if (us != NULL)
        flush (us->s);
    }
}