#include <stdio.h>
#include <unistd.h>
#include <poll.h>

#define TIMEOUT 5  /* poll timeout, in seconds */

int main(void) {
	struct pollfd fds[2];
	int ret;

	/* watch stdin for input */
	fds[0].fd = STDIN_FILENO;
	fds[0].events = POLLIN;

	/* watch stdout for ability to write (almost always true) */
	fds[1].fd = STDOUT_FILENO;
	fds[1].events = POLLOUT;

	/* All set, block! */
	ret = poll(fds, 2, TIMEOUT * 1000);
	if (ret == -1) {
		perror("poll");
		return 1;
	}

	if (!ret) {
		printf("%d seconds elapsed.\n", TIMEOUT);
		return 0;
	}

	if (fds[0].revents & POLLIN)
		printf("stdin is readable\n");
	
	if (fds[1].revents & POLLOUT)
		printf("stdout is writable\n");

	return 0;
}