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/***************************************************************
LanceMan's quickplot --- a fast interactive 2D plotter
Copyright (C) 1998, 1999 Lance Arsenault
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; version 2
of the License.
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Or look at http://www.gnu.org/copyleft/gpl.html .
**********************************************************************/
/* $Id: check_for_stdin.c,v 1.1 1998/02/28 18:09:06 lance Exp $ */
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#define WAIT_SECONDS 2
int check_for_stdin(void)
{
fd_set rfds;
struct timeval tv;
/* Watch stdin (fd 0) to see when it has input. */
FD_ZERO(&rfds);
FD_SET(0, &rfds);
/* Wait up to (tv.tv_sec) seconds and (tv.tv_usec) micro seconds . */
tv.tv_sec = WAIT_SECONDS;
tv.tv_usec = 0;
/* Don't rely on the value of tv now! */
if (select(1, &rfds, NULL, NULL, &tv))
/* printf("Data is available now.\n");*/
/* FD_ISSET(0, &rfds) will be true */
return 1;
else
/* printf("No data within %d seconds.\n",tv.tv_sec);*/
return 0;
}
#if(0) /* test program */
/* cc -o test check_for_stdin.c */
main()
{
printf("check_for_stdin() = %d\n",check_for_stdin());
}
#endif
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