The NFS protocol itself didn't disallow slashes in file names, so the NFS server would accept them without question from any client, silently corrupting the file system without any warning. Thanks, NFS!
Oh and here's a great party trick that will totally blow your mind:
On a Mac, use the Finder to create a folder or file whose name is today's date, like "2022/06/21", or anything with a slash in it. Cool, huh? Bet you didn't think you could do that!
Now open a shell and "ls -l" the directory containing the file you just created with slashes in it name. What just happened there?
Now try creating a folder or file whose name is the current time, or anything with colons, like "10:35:43". Ha ha!
Don't worry, it's totally harmless and won't trash your file system or backups like NFS with a Gator Box would.
https://news.ycombinator.com/item?id=20007875
DonHopkins on May 25, 2019 | parent | context | favorite | on: Why Does Windows Really Use Backslash as Path Sepa...
There used to be a bug in the GatorBox Mac Localtalk-to-Ethernet NFS bridge that could somehow trick Unix into putting slashes into file names via NFS, which appeared to work fine, but then down the line Unix "restore" would totally shit itself.
That was because Macs at the time (1991 or so) allowed you to use slashes (and spaces of course, but not colons, which it used a a path separator), and of course those silly Mac people, being touchy feely humans instead of hard core nerds, would dare to name files with dates like "My Spreadsheet 01/02/1991".
https://en.wikipedia.org/wiki/GatorBox
Unix-Haters Handbook
https://archive.org/stream/TheUnixHatersHandbook/ugh_djvu.tx...
Don't Touch That Slash!
UFS allows any character in a filename except for the slash (/) and the ASCII NUL character. (Some versions of Unix allow ASCII characters with the high-bit, bit 8, set. Others don't.)
This feature is great — especially in versions of Unix based on Berkeley's Fast File System, which allows filenames longer than 14 characters. It means that you are free to construct informative, easy-to-understand filenames like these:
1992 Sales Report
Personnel File: Verne, Jules
rt005mfkbgkw0 . cp
Unfortunately, the rest of Unix isn't as tolerant. Of the filenames shown above, only rt005mfkbgkw0.cp will work with the majority of Unix utili- ties (which generally can't tolerate spaces in filenames).
However, don't fret: Unix will let you construct filenames that have control characters or graphics symbols in them. (Some versions will even let you build files that have no name at all.) This can be a great security feature — especially if you have control keys on your keyboard that other people don't have on theirs. That's right: you can literally create files with names that other people can't access. It sort of makes up for the lack of serious security access controls in the rest of Unix.
Recall that Unix does place one hard-and-fast restriction on filenames: they may never, ever contain the magic slash character (/), since the Unix kernel uses the slash to denote subdirectories. To enforce this requirement, the Unix kernel simply will never let you create a filename that has a slash in it. (However, you can have a filename with the 0200 bit set, which does list on some versions of Unix as a slash character.)
Never? Well, hardly ever.
Date: Mon, 8 Jan 90 18:41:57 PST
From: sun!wrs!yuba!steve@decwrl.dec.com (Steve Sekiguchi)
Subject: Info-Mac Digest V8 #3 5
I've got a rather difficult problem here. We've got a Gator Box run-
ning the NFS/AFP conversion. We use this to hook up Macs and
Suns. With the Sun as a AppleShare File server. All of this works
great!
Now here is the problem, Macs are allowed to create files on the Sun/
Unix fileserver with a "/" in the filename. This is great until you try
to restore one of these files from your "dump" tapes, "restore" core
dumps when it runs into a file with a "/" in the filename. As far as I
can tell the "dump" tape is fine.
Does anyone have a suggestion for getting the files off the backup
tape?
Thanks in Advance,
Steven Sekiguchi Wind River Systems
sun!wrs!steve, steve@wrs.com Emeryville CA, 94608