Subject: bug#8587: Curious bug.

From: Davide Brini <[email-masked]>
Date: Fri, 29 Apr 2011 22:30:08 +0100

On Fri, 29 Apr 2011 21:09:43 +0200
Francois Boisson <[email-masked]> wrote:

> On a debian squeeze amd64.
> 
> francois@totoche:~$ echo ABCD Directory | tr [:lower:] [:upper:] 
> ABCD DIRECTORY
> francois@totoche:~$ cd /tmp
> francois@totoche:/tmp$ echo ABCD Directory | tr [:lower:] [:upper:] 
> tr: construit [:upper:] et/ou [:lower:] mal aligné
> francois@totoche:/tmp$ echo ABCD Directory | tr [:upper:] [:lower:] 
> llll lirectory
> francois@totoche:/tmp$ cd
> francois@totoche:~$ echo ABCD Directory | tr [:upper:] [:lower:] 
> abcd directory
> francois@totoche:~$ 

Not a bug.

[:upper:] and [:lower:] are also shell patterns, and if a file in the
current directory matches them, they are expanded before tr sees them.
My guess is that you have a file named "l" under /tmp, so what tr sees is

$ echo ABCD Directory | tr l [:upper:] 
tr: misaligned [:upper:] and/or [:lower:] construct

$ echo ABCD Directory | tr [:upper:] l
llll lirectory

([:upper:], as a shell pattern, matches the characters ":", "u", "p", "e"
and "r"; [:lower:] matches the characters ":", "l", "o", "w", "e" and "r").

The solution, of course, is to protect the patterns from the shell by
quoting them:

$ echo ABCD Directory | tr '[:lower:]' '[:upper:]' 
ABCD DIRECTORY

-- 
D.