Function main

examples/reg-wait.c:57–194

}

int main(int argc, char *argv[])
{
	struct io_uring_reg_wait *reg;
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe[2];
	struct io_uring ring;
	char b1[8], b2[8];
	unsigned long msec;
	struct timeval tv;
	int ret, fds[2];
	int page_size;

	if (argc > 1) {
		fprintf(stdout, "%s: takes no arguments\n", argv[0]);
		return 0;
	}

	page_size = sysconf(_SC_PAGESIZE);
	if (page_size < 0) {
		fprintf(stderr, "sysconf(_SC_PAGESIZE) failed\n");
		return 1;
	}

	if (pipe(fds) < 0) {
		perror("pipe");
		return 1;
	}

	ret = io_uring_queue_init(8, &ring, IORING_SETUP_R_DISABLED);
	if (ret) {
		fprintf(stderr, "Queue init: %d\n", ret);
		return 1;
	}

	/*
	 * Setup a region we'll use to pass wait arguments. It should be
	 * page aligned, we're using only first two wait entries here and
	 * the rest of the memory can be reused for other purposes.
	 */
	reg = t_aligned_alloc(page_size, page_size);
	if (!reg) {
		fprintf(stderr, "allocation failed\n");
		return 1;
	}

	ret = register_memory(&ring, reg, page_size);
	if (ret) {
		if (ret == -EINVAL) {
			fprintf(stderr, "Kernel doesn't support registered waits\n");
			return 1;
		}
		fprintf(stderr, "Registered wait: %d\n", ret);
		return 1;
	}

	ret = io_uring_enable_rings(&ring);
	if (ret) {
		fprintf(stderr, "io_uring_enable_rings failure %i\n", ret);