ioctl example

ioctl_example.py

import fcntl
import os

CD_DEVICE = '/dev/cdrom'
CD_EJECT = 0x5309 # From https://github.com/torvalds/linux/blob/master/include/uapi/linux/cdrom.h

# You need to open the device, not the link
if os.path.islink(CD_DEVICE):
    device_path = os.readlink(CD_DEVICE)
    if not device_path.startswith('/'):
        device_path = os.path.dirname(CD_DEVICE) + '/' + device_path
else:
    device_path = CD_DEVICE

device_fd = os.open(device_path, os.O_RDONLY | os.O_NONBLOCK )
fcntl.ioctl(device_fd, CD_EJECT, 0)
os.close(device_fd)