file globbing in now case insensitive?

[Ralf Mardorf]

On Sun, 2 Apr 2017 10:12:32 -0400, Peter Silva wrote:
>After deleting a bunch of files by mistake, I've tried this on two
>different ubuntu 16.04's, and it works the same, but I don't
>understand why. Normally, file globbing is case sensitive. so:
>
>blacklab% mkdir /tmp/kk
>blacklab% cd /tmp/kk
>blacklab% ls
>blacklab% touch A b 1
>blacklab% ls -al
>total 1060
>drwxrwxr-x  2 peter peter    4096 Apr  2 10:08 .
>drwxrwxrwt 15 root  root  1081344 Apr  2 10:08 ..
>-rw-rw-r--  1 peter peter       0 Apr  2 10:08 1
>-rw-rw-r--  1 peter peter       0 Apr  2 10:08 A
>-rw-rw-r--  1 peter peter       0 Apr  2 10:08 b
>blacklab% echo [A-Z]*
>A b
>blacklab%
>
>Huh?  this should only have listed A, but I got b as well...
> what's going on?
>
>blacklab% shopt | grep -i case
>nocaseglob     off
>nocasematch     off
>blacklab%
>
>I can't do case sensitive file globbing any more... no matter what
>settings are applied...  this is overcoming how things have worked for
>30 years... what's going on?

[rocketmouse at archlinux test]$ ls
A  b
[rocketmouse at archlinux test]$ echo [a-z]
A b
[rocketmouse at archlinux test]$ echo [[:lower:]]
b

"[snip]
 @barlop: The behavior of character ranges depends on the locale,
specifically the LC_COLLATE setting In some (many?) locales, [a-z]
includes "aAbB...yYz" but not "Z". You can enable extended globbing
using shopt -s extglob. I get different results for [a-z] and
[[:lower:]] on Cygwin. – Dennis Williamson Mar 1 '11 at 14:44 add a

It's not regexp, which is where the confusion comes in. Instead, it
uses a system called "globbing" - see:

$ man 7 glob

Instead of [a-z] you need to use [[:lower:]] as such:

$ ls -d [[:lower:]]*

[snip]"
- https://superuser.com/questions/251777/ls-or-regex-is-case-insensitive

-- 
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