Bug in "sort 2.0"

[Ruy Exel]

Dear Maintainer of Gnu text utilities,

I think I found a bug in "sort 2.0".  It is folding lower case to
upper case characters even if the -f option is not present.  In fact
it does not seem possible to make it act as is the -f option is
absent.  Below you will find the transcript of a shell session in
which the bug appears.

Sincerely,
Ruy Exel

------------------------------------------------------------------------
% echo z\\na\\nZ\\nA
z
a
Z
A
% echo z\\na\\nZ\\nA | sort -f
A
a
Z
z
% echo z\\na\\nZ\\nA | sort
A
a
Z
z
% sort --version
sort (GNU textutils) 2.0
Written by Mike Haertel.

Copyright (C) 1999 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
% sort --help
Usage: sort [OPTION]... [FILE]...
Write sorted concatenation of all FILE(s) to standard output.

  +POS1 [-POS2]    start a key at POS1, end it *before* POS2 (obsolescent)
                     field numbers and character offsets are numbered
                     starting with zero (contrast with the -k option)
  -b               ignore leading blanks in sort fields or keys
  -c               check if given files already sorted, do not sort
  -d               consider only [a-zA-Z0-9 ] characters in keys
  -f               fold lower case to upper case characters in keys
  -g               compare according to general numerical value, imply -b
  -i               consider only [\040-\0176] characters in keys
  -k POS1[,POS2]   start a key at POS1, end it *at* POS2
                     field numbers and character offsets are numbered
                     starting with one (contrast with zero-based +POS form)
  -m               merge already sorted files, do not sort
  -M               compare (unknown) < `JAN' < ... < `DEC', imply -b
  -n               compare according to string numerical value, imply -b
  -o FILE          write result on FILE instead of standard output
  -r               reverse the result of comparisons
  -s               stabilize sort by disabling last resort comparison
  -t SEP           use SEParator instead of non- to whitespace transition
  -T DIRECTORY     use DIRECTORY for temporary files, not $TMPDIR or /tmp
  -u               with -c, check for strict ordering;
                   with -m, only output the first of an equal sequence
  -z               end lines with 0 byte, not newline, for find -print0
      --help       display this help and exit
      --version    output version information and exit

POS is F[.C][OPTS], where F is the field number and C the character position
in the field, both counted from one with -k, from zero with the obsolescent
form.  OPTS is made up of one or more of Mbdfinr; this effectively disables
global -Mbdfinr settings for that key.  If no key is given, use the entire
line as the key.  With no FILE, or when FILE is -, read standard input.

Report bugs to <address@hidden>.
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