#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <termios.h>
#include <poll.h>
#include <string.h>
#include <errno.h>

struct termios tsav;

void
dump(fd, save)
	int fd;
{
	struct termios t;
	int res;

	res = tcgetattr(fd, &t);
	if (res < 0)
		exit(errno);

	if (save)
		tsav = t;

	fprintf(stderr, "fd %d: %x/%d/%d\n", fd, t.c_iflag,
		t.c_cc[VMIN], t.c_cc[VTIME]);
}

void
setraw(fd)
	int fd;
{
	struct termios t;
	int res;

	res = tcgetattr(fd, &t);
	if (res < 0)
		exit(errno);
	cfmakeraw(&t);
	t.c_cc[VMIN] = 4;
	t.c_cc[VTIME] = 1;
	res = tcsetattr(fd, TCSAFLUSH, &t);
	if (res < 0)
		exit(errno);
}

void
restore(fd)
	int fd;
{

	tcsetattr(fd, TCSAFLUSH, &tsav);
}

int
main()
{
	int in;
	int flags, res;
	struct pollfd inp;
	char buf[100];

	in = STDIN_FILENO;

	flags = fcntl(in, F_GETFL);
	if (flags == -1)
		exit(errno);
	flags |= O_NONBLOCK;
	res = fcntl(in, F_SETFL, flags);
	if (res < 0)
		exit(errno);

	dump(in, 1);
	setraw(in);
	dump(in, 0);

	inp.fd = in;
	inp.events = POLLIN;
	res = poll(&inp, 1, -1);
	fprintf(stderr, "poll: %d (%s)\n", res, strerror(errno));
	res = read(in, buf, sizeof(buf));
	fprintf(stderr, "read: %d (%s)\n", res, strerror(errno));

	restore(in);
	exit(0);
}