Hello Team, May I please know the reason for the following behaviour of the sort command... ------------------ 0 $ sort -k 2 bug2_file2 512 b1 512 b101 0 $ sort bug2_file1 b101 512 b1 512 0 $ sort -k 1 bug2_file1 b101 512 b1 512 ------------------ The output is same with options '-s', '-g', '-n', '-d' (used one at a time) also. ------------------ 0 $ sort --version sort (GNU coreutils) 5.97 Copyright (C) 2006 Free Software Foundation, Inc. This is free software. You may redistribute copies of it under the terms of the GNU General Public License . There is NO WARRANTY, to the extent permitted by law. Written by Mike Haertel and Paul Eggert. Regards, Krishna