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> Extensions are not for average computer users. They have icons and filenames. Windows also hides extensions by default. As far as I recall, extensions became
by throwaway201103 6y ago
> Extensions are not for average computer users. They have icons and filenames. Windows also hides extensions by default.
As far as I recall, extensions became a thing with DOS. They actually had meaning to the OS, e.g. naming a file .exe would make it executable, as there was no other concept of file ownership or permissions.
In Unix/Linux systems, filename extensions have always been for the user. Before GUIs and icons, they were a convention that let the user know something about the file contents. As far as the operating system is concerned, "." is just another character in the name and extensions are meaningless. Note that most binary executables don't have an extension at all, and other files have more than one (e.g. .tar.gz)
- reaperducer 6y agoAs far as I recall, extensions became a thing with DOS CP/M had extensions in 1974, five years before DOS. There may be older examples, but that's the first operating system I ever used.
- throwaway201103 6y agoMakes sense. I think DOS took a lot of inspiration from CP/M.
- wglb 6y agoAnd PDP-10 had them back in the 70s
- lokedhs 6y agoPDP-10 was an architecture, and there were many operating systems running on them. You may be thinking of TOPS-20, which indeed used filename.ext, where the extension was limited to 3 characters. There was also ITS, which was one of the famous operating systems on the PDP-10. On ITS, filenames consisted of two parts, rach being 6 characters separated with a space. So you could have a file named "abc def". The second half was often used in the same way we use extensions today, but executable files were named "ts name", where name was the name of the command. I'm not sure what format filenames had on TENEX and TOPS-10.
- wglb 6y agoVery good point. I was referencing Tops-10, which I am the most familiar with.