Writing starting from a certain line number in a text file

Question

In a bash script I want to write some lines to a text file, but this file has already been used before and there are texts in it. So I want to echo some additional text in it, starting from a certain line number in the file.

I want something like this:

echo -fromLineNumber 33 -e "anything" >> textPath

kumarprd · Accepted Answer · 2013-05-14T17:59:44.223

21

You can use sed to write at a particular line.

try this:

    sed -i '33ianything' textpath

or

    sed -i '33i\anything' textpath

It will insert "anything" in line number 33.

edited May 14 '13 at 17:59

answered May 14 '13 at 17:35

kumarprd

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It should work. Works fine for me in bash 4.2 and sed 4.2 in ubuntu. – kumarprd May 14 '13 at 17:55
1

wait a minute i will try again – Ahmed Zain El Dein May 14 '13 at 17:57
Thanks it works , it was my mistake in the first place thank u very much – Ahmed Zain El Dein May 14 '13 at 17:59
can i write it like this `sed -i '$numberkanything' textPath` out i must write down the number of line directly – Ahmed Zain El Dein May 14 '13 at 18:43
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@AhmedZainElDein, the shell will not expand variables within single quotes. Also you have to tell the shell how to differentiate the variable name from the following text: `sed -i "${number}i\anything" file` – glenn jackman May 14 '13 at 21:36
in case anything was a variable value also the \ will make a problem to the $ in case i want to use the one with \ `sed -i "${number}i\$anything" file` so any idea about how to skip that – Ahmed Zain El Dein May 14 '13 at 22:25

score 2 · Answer 2 · answered May 14 '13 at 17:24

2

To keep the first 32 lines and add new text afterwards:

head -n 32 oldfile > newfile
echo anything >> newfile
echo goes >> newfile
echo here >> newfile

To insert some text after line 32 of a file:

sed -e '32s/$/\nanything\ngoes\nhere/' oldfile > newfile

answered May 14 '13 at 17:24

frostschutz

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thank u , but i want to append on the old text file my new texts after a certain line number not to add in new file , i hope that i can make myself clear? – Ahmed Zain El Dein May 14 '13 at 17:28

Writing starting from a certain line number in a text file

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