Copy some line and paste it after some line in same file

Shell Programming and Scripting
1

Hi,

I want to know how I can copy line 6th to 10th and paste it after 17th line in same file.

Thanks,
Biplab

2

Does copy mean to overwrite line 10 with line 6 or insert it there so that line 10 becomes line 11? For line 17, what should be appended there, line 6 or 10?

3

I want to say that...
if

1 a
2 b
3 c
4 d
5 e
6 f
7 g

now if i copy from 2nd line to 4th line and paste it before 6th line.. o/p will be

1 a
2 b
3 c
4 d
5 e
2 b
3 c
4 d
6 f
7 g

I want to know the command to do that..

4

Homework ?

5

Asked in a Interview of top MNC company...:slight_smile:

6

If using sed is an option, try:

sed '2,4H;6{;x;s/^\n//;p;x;}' file
7

Is it batch or interactive (sed/awk stuff agains pure vi...) ?

8

Could you please explain how this works? I'm curious

9

You should know the concept of pattern and hold spaces to understand this. You should also know the following sed sub-commands:

H --> append contents of pattern space to hold space
x --> exchange/swap contents of pattern space and hold space

So, in brief,
2,4H --> for lines from 2 to 4, append the pattern space to hold space.
6{;x;s/^\n//;p;x;} --> at line 6, swap the pattern and hold spaces (at this juncture, hold space looks like \n2 b\n3 c\n4 d ) to hold line 6. Delete the first new-line in this new pattern space so that you do not get a blank line in the output. Then, print this pattern space. Last, swap pattern and hold spaces again so that line 6 is printed.

1 Like
10

Hello Siniri,

Code is not working properly for me... could you please explain the code??

Thanks,
Biplab

11

What does that mean? Could you post the output you got by running the command on your sample file?

I've already done that.

12 
cat test
1 a
2 b
3 c
4 d
5 e
6 f
7 g

sed '2,4H;6{;x;s/^\n//;p;x;}' test

1 a
2 b
2 b
3 c
3 c
2 b
3 c
4 d
4 d
2 b
3 c
4 d
6 f
2 b
3 c
4 d
7 g
13

Hi,

Check this out,

awk 'NR>=6 && NR <=10{if(s){s=s RS $0;}else{s=$0}next;}NR==18{print s;}1' file

Cheers,
Ranga :slight_smile:

14

Hi Ranga,

Just one small addition...

awk 'NR>=6 && NR <=10{if(s){s=s RS $0;print;}else{s=$0}next;}NR==18{print s;}1' file
15

Hmm..you seem to have to made some mistake while running the command (may be changed the positions of the semicolons). Try with this and let me know:

sed '2,4H
6{
x
s/^\n//
p
x
}' test
1 Like
16

Nope mate :slight_smile:

I think, you are trying to print all the original content and also print those content(6-10 lines) after the specified line(17th). If yes,
Then probably you have to remove the next,

awk 'NR>=6 && NR <=10{if(s){s=s RS $0;}else{s=$0}next;}NR==18{print s;}1' file1

Cheers,
Ranga :slight_smile:

1 Like
17

Got it Ranga...:slight_smile:

Thanks a lot:)

My try on this..:smiley:

awk '{if ((NR>=6) && (NR<=10)){{if(s){s=s RS $0;print;}else{s=$0}}}else{if (NR ==18){s=s RS $0; print s} else{ print;}}}' file
18

Much appreciated for your tries.
I think you have to finetune the script :slight_smile:

Cheers,
Ranga :slight_smile:

19

Yes, Its working fine now... Thanks :slight_smile:

20

Hi.

A solution using ed:

#!/usr/bin/env bash

# @(#) s1	Demonstrate scripted interactive editor, ed.

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
edges() { local _f _n _l;: ${1?"edges: need file"}; _f=$1;_l=$(wc -l $_f);
head -${_n:=3} $_f ; pe "--- ( $_l: lines total )" ; tail -$_n $_f ; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C ed paste

FILE=${1-data1}

pl " Input data file $FILE:"
cat $FILE
cp $FILE working

pl " Results, calculated vs desired:"
ed working 2>/dev/null <<'EOF'
2,4y
5x
w
q
EOF
if cmp working expected-output.txt
then
  paste working expected-output.txt
else
  pe " Error in calcualtion."
fi

exit 0

producing:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.8 (lenny) 
bash GNU bash 3.2.39
ed GNU Ed 0.7
paste (GNU coreutils) 6.10

-----
 Input data file data1:
1 a
2 b
3 c
4 d
5 e
6 f
7 g

-----
 Results, calculated vs desired:
1 a	1 a
2 b	2 b
3 c	3 c
4 d	4 d
5 e	5 e
2 b	2 b
3 c	3 c
4 d	4 d
6 f	6 f
7 g	7 g

See man ed for details ... cheers, drl