/* Pipe to a Subprocess

   Copyright (C) 1991-2018 Free Software Foundation, Inc.

   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

   of the License, 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, if not, see <http://www.gnu.org/licenses/>.

*/

#include <stdio.h>

#include <stdlib.h>

void

write_data (FILE * stream)

{

  int i;

  for (i = 0; i < 100; i++)

    fprintf (stream, "%d\n", i);

  if (ferror (stream))

    {

      fprintf (stderr, "Output to stream failed.\n");

      exit (EXIT_FAILURE);

    }

}

/*@group*/

int

main (void)

{

  FILE *output;

  output = popen ("more", "w");

  if (!output)

    {

      fprintf (stderr,

	       "incorrect parameters or too many files.\n");

      return EXIT_FAILURE;

    }

  write_data (output);

  if (pclose (output) != 0)

    {

      fprintf (stderr,

	       "Could not run more or other error.\n");

    }

  return EXIT_SUCCESS;

}

/*@end group*/