Shell Programming and Scripting

Thanks a lot Yoda....the awk code is working fine and showing me the exact result what I'm expecting. Thanks a lot.

A few thoughts regarding your solution ...

Most sed implementations do not recognize the "\n" escape sequence in replacement text. Typically, a backslash followed by a newline is required.

The \1 backreference isn't necessary, since the entirety of the matching text is all that's needed and sed already makes that available via &.

You don't need to use uniq. sort -u will do the job.

grep isn't necessary. Since you are already using sed, you can use it to delete blanks at the start.

An untested variation of your approach:

Code:

sed 's/ //g; /./!d; s/./&\
/g; s/.$//' file | sort -u

Equally untested code:

Code:

tr -d ' \b\t\r' < file | fold -w1 | sort -u

Regards,
Alister

Thank you for the thoughtful suggestions.

The backslash would prevent a literal newline from being fed into sed. Leave it off.

Code:

$ echo "a\
b"

ab

$ echo "a
b"

a
b

$

You are mistaken. To portably insert a newline in sed replacement text, a backslash-newline pair is required.

From POSIX sed:
What you are demonstrating is sh line continuation. This is unrelated to the requirements of a sed script.

Regards,
Alister