Re: [Gnu-arch-users] Re: tla1.2 on cygwin

[David A. Wheeler]

Aaron Bentley <address@hidden> wrote:
> Personally, I think people who use capital letters in their filenames 
> are wierdos, and I'd be happy if this was solved by requiring that all 
> category/branch names are lowercase.

Tom Lord replied:
> [That's] A perfectly reasonable _convention_ to promote.

and Erik de Castro Lopo replied:
> Well I'm one of those weirdos, but it certainly wouldn't break my heart
> if it became policy to for all lowercase category and branch names as 
> long as there was an easy way to transition from what i have now.


Here's an idea: why not reject making NEW categories, branches
(and maybe archives?) with the uppercase letters A-Z, unless some option like
"--force" is added?  Without "--force", an error message could be
printed like this:
"Using names with uppercase letters A-Z is not recommended, because
many broken filesystems (like FAT and NTFS) map upper and lowercase letters
together; the resulting confusion can risk data corruption.
Use the lowercase letters a-z instead of A-Z, to avoid these problems.
If you are sure you want to use the uppercase letters A-Z, use the --force 
option
to overrid this."

Since it only affects creating NEW categories/branches (and archive names?),
it won't affect using any current ones.  And if you know that won't
be a problem, you can override.

So, it's a convention strongly encouraged by the tool, but easily
overridden if you don't agree.

Other solutions might be better.  But this has the advantage of
stark simplicity, while avoiding some data corruption problems.
Anybody reading that error message will quickly understand why their request
was rejected; no need to read a complicated user manual on the non-joys
of case-insensitive filesystems (the majority of all running filesystems, sigh).
This approach won't interfere with international characters at all, a good 
thing.
And yet, this simple test will mean that the tool will protect
users from subtle disasters, with a way to override the protection if you
know what you're doing.

BTW, I limited this to A-Z.  Perhaps it shouldn't permit
"uppercase letters" in general, but I bet the various case-folding
filesystems aren't that smart.  I'll bet they do A-Z => a-z and
nothing more, because of the complexities of international languages.

I don't know if archive names should be limited to forbid A-Z.
They probably SHOULD be, for all the same reasons.
If so, that means -MIRROR needs to be -mirror.
That doesn't appear to be a serious problem to me, but others
might disagree.  Note this has nothing to do with the filenames
of where things are stored, or of the files that are managed.

--- David A. Wheeler