#include <errno.h>
#include <fcntl.h>
#include <stdio.h>

#include <unistd.h>
#include <linux/cdrom.h>
#include <sys/ioctl.h>

int main(void)
{
	// Open cdrom device, it must be opened in non-blocking mode
	int cdfd = open("/dev/cdrom", O_RDONLY | O_NONBLOCK);
	if (cdfd < 0) {
		perror("open");
		return 1;
	}

	int cdrom_stat = ioctl(cdfd, CDROM_DRIVE_STATUS, 0);

	if ((cdrom_stat > -1 && cdrom_stat != CDS_NO_INFO) &&
		cdrom_stat == CDS_TRAY_OPEN) {
		printf("tray is already open\n");
		return 0;
	}

	// Issue eject command
	if (ioctl(cdfd, CDROMEJECT, 0) < 0) {
		if (errno == EBUSY) {
			fputs("either another process is using the drive or the door is locked.\n", stderr);
			return 1;
		}
		perror("ioctl");
		return 1;
	}

	close(cdfd);
	return 0;
}