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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

2 Answers 2

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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.

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  • It should work. Works fine for me in bash 4.2 and sed 4.2 in ubuntu.
    – kumarprd
    May 14, 2013 at 17:55
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    wait a minute i will try again
    – Ahmed Zain El Dein
    May 14, 2013 at 17:57
  • Thanks it works , it was my mistake in the first place thank u very much
    – Ahmed Zain El Dein
    May 14, 2013 at 17:59
  • can i write it like this sed -i '$numberkanything' textPath out i must write down the number of line directly
    – Ahmed Zain El Dein
    May 14, 2013 at 18:43
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    @AhmedZainElDein, the shell will not expand variables within single quotes. Also you have to tell the shell how to differentiate the variable name from the following text: sed -i "${number}i\anything" file
    – glenn jackman
    May 14, 2013 at 21:36
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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
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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, 2013 at 17:28

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