Documentation/usb/gadget_printer.rst

208 	struct pollfd	fd[1];
211 	fd[0].fd = open(PRINTER_FILE, O_RDWR);
212 	if (fd[0].fd < 0) {
213 		printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
214 		close(fd[0].fd);
218 	fd[0].events = POLLIN | POLLRDNORM;
226 		retval = poll(fd, 1, 1000);
228 		if (retval && (fd[0].revents & POLLRDNORM)) {
231 			bytes_read = read(fd[0].fd, buf, BUF_SIZE);
235 						fd[0].fd, PRINTER_FILE);
236 				close(fd[0].fd);
249 	close(fd[0].fd);
258 	struct pollfd	fd[1];
261 	fd[0].fd = open (PRINTER_FILE, O_RDWR);
262 	if (fd[0].fd < 0) {
263 		printf("Error %d opening %s\n", fd[0].fd, PRINTER_FILE);
264 		close(fd[0].fd);
268 	fd[0].events = POLLOUT | POLLWRNORM;
283 			retval = poll(fd, 1, 1000);
286 			if (retval && (fd[0].revents & POLLWRNORM)) {
287 				retval = write(fd[0].fd, buf, bytes_read);
290 							fd[0].fd,
292 					close(fd[0].fd);
305 	fsync(fd[0].fd);
308 	close(fd[0].fd);
317 	int		fd;
322 	fd = open(PRINTER_FILE, O_RDWR|O_NONBLOCK);
323 	if (fd < 0) {
324 		printf("Error %d opening %s\n", fd, PRINTER_FILE);
325 		close(fd);
331 		bytes_read = read(fd, buf, BUF_SIZE);
342 	close(fd);
352 	int	fd;
355 	fd = open(PRINTER_FILE, O_RDWR);
356 	if (fd < 0) {
357 		printf("Error %d opening %s\n", fd, PRINTER_FILE);
358 		close(fd);
363 	retval = ioctl(fd, GADGET_GET_PRINTER_STATUS);
370 	close(fd);
380 	int	fd;
389 	fd = open(PRINTER_FILE, O_RDWR);
391 	if (fd < 0) {
392 		printf("Error %d opening %s\n", fd, PRINTER_FILE);
393 		close(fd);
404 	if (ioctl(fd, GADGET_SET_PRINTER_STATUS, (unsigned char)retval)) {
410 	close(fd);