Subject: Re: "Illegal" characters.

From: [email-masked] (Robert Perlberg)
Date: 26 May 94 20:55:45 GMT

On Sat, 21 May 1994, Christopher "AWOL" Curtis wrote:
>   I have created a folder which I call "for sale."  In it I keep, not 
> surprisingly, items that are for sale.  Now, whenever I enter this 
> folder, after a short interval PINE tells me that:
>     "[Character '<space>' after 'for' not allowed in folder name]"
> which is obviously false as I have no troubles whatsoever accessing this 
> directory.  I was just curious as to why the functionality exists for 
> this popup message.

I've always considered it a major omission that Unix does not enforce
the use of a limited character set for file names.  It should not have
been hard to implement early on.  There is probably only one (if not
just a few) place in the system where file names are created (file
creation, link, etc.).  It should not have been hard to do a scan on
the file name for "illegal" characters and bomb the system call.
Unfortunately, this was not done and there are now far too many funky
file names out there that would become inaccessible if the feature were
added now.  The reason I think the lack of this feature is such a bad
idea is that it creates problems with lots of commands.  File names
with spaces or shell metacharacters in them have to be quoted when used
as arguments on command lines, and many scripts do not do the necessary
quoting (for which I do not blame them since it's an excessively
bothersome thing to have to do) making many facilities unusable with
such files, not to mention that there are some scripts which bomb
completely or create garbage files when they come across these file
names.  Given that Pine was designed for the casual user who is not
expected to be mindful of such concerns, it makes sense that they
designed it to disallow file names which would cause such problems.

Robert Perlberg
Dean Witter Reynolds Inc., New York
[email-masked] -or- [email-masked]
	-- "I am not a language ... I am a human being!"

---

From: [email-masked] (Barry Shein)
Date: Thu, 26 May 1994 18:35:08 -0400

From: [email-masked] (Robert Perlberg)
>the file name for "illegal" characters and bomb the system call.

It was done on purpose so the file system could support other
character sets, like Kanji.

In fact, the rules were liberalized over the years. Originally a lot
of unix systems wouldn't allow the 8th bit on in file name
characters. This was decided to be a botch and was fixed. There are
other examples.

Modern unix file systems only disallow / and NULL in file names
(sometimes you can slip a / thru tho that tends to be a problem.)

It's a feature not a bug.

        -Barry Shein

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