sed insert line command to add text with new line OSX

Question

I'm trying to insert text to the 100th line in a file using sed, and the syntax I've found on other forums is:

sed -i '' "100i\ text to insert" filename

When I use this I am able to add text on a particular line but it affects other text which is already there and misplaces it.

I want to add a new line before and after the text added to the file.

I tried this sed -i '' "100i\\ text to insert other text to insert" filename but it didn't work as excepted.

This is the output when I run the above command. the order should be <key> and below that should be <string> tag.

<key>NSBluetoothAlwaysUsageDescription</key>    <key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>This will allow "App" to find and connect to Bluetooth accessories. This app may also use bluetooth to know when you are nearby.</string>   <string>This app requires constant access to your location in order to track your position, even when the screen is off or the app is in the background.</string>

I can't seem to figure out what should I add in command to add a new line.

I don't want to disturb order I just want if I am inserting text at line 100 and if there is a text already then that text should go to a new line.

I'm using OSX, which is why I have an empty ' ' as my extension.

Thanks!

Answer 1

If you wish to add a newline, you should use: $'\\n' ; ANSI quoting

More SO info on sed newline

---

To answer the question; use:

sed -i '' -e "3s/^//p; 3s/^.*/text to insert/" /tmp/so.txt

1. 3s/^//p; Duplicate line #3
2. 3s/^.*/text to insert/" Replace newly line #3 with your text

Edit;

sed -i '' -e "3s/^//p; 3s/^.*/<key>NSBluetoothAlwaysUsageDescription<\/key>/" /tmp/so.txt

Remember to escape any / chars!

Answer 2

Try ed(1) if you want.

printf '%s\n' 3a 'text to insert' . w | ed -s file

Here no escaping needed.

printf '%s\n' '100a' '<key>NSBluetoothAlwaysUsageDescription</key>    <key>NSLocationAlwaysAndWhenInUseUsageDescription</key>' '<string>This will allow "App" to find and connect to Bluetooth accessories. This app may also use bluetooth to know when you are nearby.</string>   <string>This app requires constant access to your location in order to track your position, even when the screen is off or the app is in the background.</string>' . w | ed -s file.txt

... or using a Heredoc

ed -s file.txt <<'EOE'
100a
<key>NSBluetoothAlwaysUsageDescription</key>    <key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>This will allow "App" to find and connect to Bluetooth accessories. This app may also use bluetooth to know when you are nearby.</string>   <string>This app requires constant access to your location in order to track your position, even when the screen is off or the app is in the background.</string>
.
w
EOE

Just replace the file.txt with your file name.