bug#16778: Neither ls nor sort do a correct lexicographic sort

[Jarosław Rzeszótko]

Hi,

Please contemplate the following shell session:

/home/jarek # mkdir test

/home/jarek # cd test

/home/jarek/test # touch x_y.c

/home/jarek/test # touch xs.c

/home/jarek/test # ls -1
razem 0
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 xs.c
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 x_y.c

/home/jarek/test # ls -1 | sort
razem 0
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 xs.c
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 x_y.c

/home/jarek/test # ls -1 | perl -e 'print(sort(<STDIN>))'
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 x_y.c
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 xs.c
razem 0

/home/jarek/test # ls -v
razem 0
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 xs.c
-rw-r--r-- 1 jarek jarek 0 02-17 15:34 x_y.c

/home/jarek/test # ls --version
ls (GNU coreutils) 8.22

The ordering that is produced by both ls and sort is incorrect, according
to a widely accepted convention "x_y.c" preceeds "xs.c", as the perl
example illustrates. I checked this on two different distributions, so it
should not be an distribution-specific issue, rather seems a logical
mistake in coreutils itself.

Cheers,
Jarosław Rzeszótko