Why in file and folder names, are some characters still not accepted?

Question

Why files and folders still do not accept some different characters?

I believe you must have some programmatic influence in order to make that decision. The Operating Systems had and/or still have restrictions to be produced in this way?

As well as domain names that formerly did not accept accentuation and different characters, and started working with them, more recently.

An Internationalised Domain Name is a Domain name that can contain characters not defined by the ASCII standard. These characters include Most of the accented Letters used in Different European Languages and other characters that are not found in the Latin Alphabet. (i.e accentuates.with)

Technically, accented characters can not be used in DNS, which is Why Every IDN is encoded as a string of non-accented Character Whose Shape is called ACE. In the Latter, the Domain Names Begin with XN - to differentiate unaccented Domain Names. (i.e : Xn-accentus-h1a.com)

(excerpt from here)

Example:

The Domain name ːΩ converted into ACE chain is Xn-cba88bf7c

In that article of W3 talks a little about this "internationalization" of domains

User’s expectations and use of the Internet have Moved on Since then, and there is now a Growing need to enable use of characters from any language in Web Addresses. A Web address in your Own language and Alphabet is easier to create, memorize, transcribe, interpret, Guess, and relate to. It is also Important for Brand recognition. This, in turn, is Better for business, Better for finding Things, and Better for communicating. In short, Better for the Web.

I believe this question touches more on the history of creation (so it has a little to do with programming) of operating systems.

Answer 1

Basically it is a problem of ambiguity in Parsing. It’s a problem similar to what we have in strings in languages where some characters are special, such as the quotation marks themselves, the backslash and the percentage or keys, etc.

These characters have a meaning in operating system commands, in the case of MS-DOS initially and then Windows. Unixes have another character set that cannot be used.

They could have been smarter and allowed those characters in quotes, and even it could have been used with a escape. But they didn’t. It’s also not a big problem. It probably doesn’t change because it’s not an important need.

• / - indicator of flag of command
• \ - folder separator
• : - volume separator
• * - joker to indicate any name
• ? - joker to indicate any character
• " - text delimiter (names that have space need it)
• < - input driver
• > - output driver
• | - outgoing plumbing

It’s not about accentuation, which is allowed.