// Flush: yield any remaining data
Recall that kernel events were not the thing we were actually interested in. We wanted udev's version of the events. Browsing through libudev's source code, we can see that udev events are also broadcast using netlink. Even though netlink is often used to communicate with the kernel, NETLINK_KOBJECT_UEVENT allows for userspace-to-userspace communication. We just have to change the multicast group in our sample program to MONITOR_GROUP_UDEV which is 2.
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This approach could be used with any REPL environment. Code cells could be different languages/runtimes that execute independently. We could even go a step further and create an IPC layer between these language runtimes to create polyglot notebooks.
The telephoto camera alone is also technically interesting in a few ways. It offers continual optical zoom across the 75-100mm range without in-sensor cropping. This means the lenses physically move to deliver lossless zoom across a range of distances, without jarring leaps between camera sensors and crops. This doesn’t run across the full gamut, but it does roughly cover the 3-4x optical zoom range, which is often used in portrait photography.