[ale] BASHing my head

[Scott Plante]

This link gives some examples of the trouble you can find when you parse ls: 


http://mywiki.wooledge.org/ParsingLs 


It doesn't mention it, but another good rule might be NEVER put newlines in your filenames! 


----- Original Message -----

From: "Jim Kinney" <jkinney at jimkinney.us> 
To: "Atlanta Linux Enthusiasts" <ale at ale.org>, "DJ-Pfulio" <DJPfulio at jdpfu.com> 
Sent: Thursday, August 27, 2015 6:56:46 AM 
Subject: Re: [ale] BASHing my head 

I've not heard that but ls output can be a challenge. Parsing ls -A1 is fun. 


On August 26, 2015 6:23:06 PM EDT, DJ-Pfulio <DJPfulio at jdpfu.com> wrote: 

I seem to recall being told to NEVER parse the output from ls - ever. 
Maybe I misunderstood? 

On 08/26/2015 05:38 PM, Jim Kinney wrote: 

<blockquote>
Yeah. What he said. 
>From my F22 bash-land (4.3.39): 
touch a.pdf A.pdf b.pdf B.pdf c.pdf C.pdf z.pdf Z.pdf 
[jkinney at dhcp061167 tmp]$ ls 
a.pdf  A.pdf  b.pdf  B.pdf  c.pdf  C.pdf  z.pdf  Z.pdf 
[jkinney at dhcp061167 tmp]$ ls | grep "[A-Z].pdf" 
A.pdf 
B.pdf 
C.pdf 
Z.pdf 
[jkinney at dhcp061167 tmp]$ ls | grep "[a-z].pdf" 
a.pdf 
b.pdf 
c.pdf 
z.pdf 
On Wed, 2015-08-26 at 15:41 -0400, Ed Cashin wrote: 

<blockquote>
I've been biting my tongue here.  I don't think these characteristics 
of bash are congrue
 nt with
UNIX philosophy.  The people who made UNIX 
complain about bash being bloated.  These characteristics of bash are 
congruent with POSIX philosophy. 

A UNIX-ish way of doing this would be ... 

ls | grep '^[A-Z].*\.pdf' 


On Wed, Aug 26, 2015 at 1:41 PM, Jim Kinney <jim.kinney at gmail.com> 
wrote: 

<blockquote>
Wow! Shopt has enough options to make it stand next to emacs. 
I don't understand why the default is essentially case insensitive 
when everything else in bash is case sensitive. It looks like the 
LANG makes it work that way but that makes no sense either to me. A 
!= a in standard US English. 
More of the secret mysteries of Unix philosophy I've never wrapped 
my head around. 
On Aug 26, 2015 12:16 PM, "Scott Plante" <splante at insightsys.com> 
wrote: 

<blockquote>
I didn't know the globasciiranges option. 

Another solution is the LC_COLLATE variable: 



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