Comments on: Unix Sed Tutorial: Multi-Line File Operation with 6 Practical Examples

By: Greg

Greg — Tue, 27 Dec 2011 23:45:29 +0000

I got example #6 working in a windows batch file as a multi-line find/replace. Many other sed multi-line examples I found online just didn’t work in all cases. But a modified example #6 like the following works:

sed –text -n -e “s|2011|&|p” -e “$^!N;/Directory.*\n.*2011/P; D” input.txt > output.txt

This sed line, running under the windows ver. of sed, finds either lines with “2011″ or lines with “Directory” only if “2011″ is on the next line, and the output is redirected to a separate file. The –text option helps generate the proper CR/LF for windows. Also, the exclamation char has to be “escaped” in a batch file *IF* enabledelayedexpansion is being used in context.

By: frankhuang

frankhuang — Thu, 18 Nov 2010 01:58:04 +0000

example 5 works because the last line is empty line, and
sed -n ‘$!h;$H;$x;$p’ thegeekstuff.txt
also works to Print Last 2 Lines of a file

By: Indraneel Nag

Indraneel Nag — Thu, 23 Sep 2010 10:45:26 +0000

How can you make multiline text file to one single line text file

By: Masood

Masood — Mon, 25 Jan 2010 23:31:46 +0000

In Example 5,the output is only last line and not last two lines.Can you confirm plz?

By: Masood

Masood — Mon, 25 Jan 2010 23:12:18 +0000

In Example 4 ,if total number of lines in sample script are even including blank lines then I think we can also use following sed command
sed ‘N;$d’ thegeekstuff.txt

By: Unix Sed Tutorial : 7 Examples for Sed Hold and Pattern Buffer Operations

Unix Sed Tutorial : 7 Examples for Sed Hold and Pattern Buffer Operations — Wed, 09 Dec 2009 06:03:25 +0000

[...] — sed printing, sed deletion, sed substitute , sed file write, sed multiple commands, sed multi-line operation, and sed manipulate file [...]

By: Destillat KW48-2009 | duetsch.info - GNU/Linux, Open Source, Softwareentwicklung, Selbstmanagement, Vim ...

Fri, 27 Nov 2009 09:37:17 +0000

[...] Unix Sed Tutorial: Multi-Line File Operation with 6 Practical Examples [...]

By: Sasikala

Sasikala — Thu, 26 Nov 2009 04:28:35 +0000

Yes Berry, you are absolutely correct.

By: Berry

Berry — Wed, 25 Nov 2009 14:41:27 +0000

In Example 2, I think the command provided in the article only works when the number of consecutive blank lines is even. Because in the left part, sed ‘/./=’ only print the line number before the non-blank line, the blank line is not changed. But in the right part, join every two lines (both non-blank and blank) into one line and substitute the \n with space. Then, if the number of consecutive blank lines in the original file is odd, that the last blank line will join the line number of next line.

For example:
aaa
blank
bbb

After the left part:
1
aaa
blank
3
bbb

So, I think the solution can be found in the left part
sed ‘/./=’ thegeekstuff.txt | sed ‘/./{
N
s/\n/ /
}’