> Explain how they don't. Simple, because the intersection of all the interfaces of these different "file" types is nothing other than close(). At that point t

> Explain how they don't. Simple, because the intersection of all the interfaces of these different "file" types is nothing other than close(). At that point the abstraction has lost all ability to describe anything common better than just OS managed object. When a noun is used as an abstraction, this is often a good benchmark of utility, better than just your arbitrary preference. File in computing may have always been an abstraction, but it started out in relation to some sort of data storage and an appropriate interface, usually also addressable by some index (a filesystem). If you have a object with open/close/read/write/seek, you at least have something. Then we drop seek, and add ioctl. Now the cracks have formed, but there is still something there, there is still data involved and things still have a common source: the file system. But at this point these other fds, the only thing common is close(). You can try to go the a different (plan 9) route, but that requires something to tie these together, a filesystem. And that is not something the systems in question have. > But in the end, words are allowed to have more than one meaning But once an abstraction has lost its usefulness people do not have to go along with the stupidity. I don't even have much care about this. Call them files. But where it is a bit irritating people still go on to say "everything is a file" when describing useful attributes of modern UNIX likes as if this illustrates some deep insight of this abstraction. This "everything" involves one operation: throwing the thing a way. It's stupid. We should retcon file as a shorthand for "roundfile".