Bash: Inserting a Line in a File at a Specific Location

Bash: Inserting a line in a file at a specific location

If you want to add a line after a specific string match:

$ awk '/master.mplayer.com/ { print; print "new line"; next }1' foo.input
ServerActors=IpServer.UdpServerUplink MasterServerAddress=unreal.epicgames.com MasterServerPort=27900
ServerActors=IpServer.UdpServerUplink MasterServerAddress=master0.gamespy.com MasterServerPort=27900
ServerActors=IpServer.UdpServerUplink MasterServerAddress=master.mplayer.com MasterServerPort=27900
new line
ServerActors=UWeb.WebServer

Insert lines in a file starting from a specific line

This can be done with sed: sed 's/fields/fields\nNew Inserted Line/'

$ cat file.txt 
line 1
line 2 
fields
line 3
another line 
fields
dkhs

$ sed 's/fields/fields\nNew Inserted Line/' file.txt 
line 1
line 2 
fields
New Inserted Line
line 3
another line 
fields
New Inserted Line
dkhs

Use -i to save in-place instead of printing to stdout

sed -i 's/fields/fields\nNew Inserted Line/'

As a bash script:

#!/bin/bash

match='fields'
insert='New Inserted Line'
file='file.txt'

sed -i "s/$match/$match\n$insert/" $file

Add a line in a specific position with Linux and output to the same file?

The only way to do this is to write to a second file, then replace the original. You can only append to an arbitrary file; you cannot insert into the middle of one.

t=$(mktemp)
sed '3iline 3' file.txt > "$t" && mv "$t" file.txt

If your version of sed supports it, you can use the -i option to automate the handling of the temporary file.

sed -i '3iline 3' file.txt  # GNU
sed -i "" '3iline 3 ' file.txt  # BSD sed requires an argument for -i

How to insert variable into file at a specified position

Perhaps try and integrate this solution using sed:

sed -i -E "s/(^hotfix\.dlFilePath\=\/opt\/files\/)(.*$)?/\1$files/" config.properties

Please note the use of double quotes around the substitution expression in sed to make the shell expand variables. So, with a variable like this

files="foo"

and given this input (assuming that the <file> was just a placeholder):

rest.server.url=https\://hostname/RestService/
rest.username=user
rest.password=pass
rest.response.type=json
hotfix.async=false
hotfix.operation=hotfix
hotfix.dlFilePath=/opt/files/

you'll get this result

rest.server.url=https\://hostname/RestService/
rest.username=user
rest.password=pass
rest.response.type=json
hotfix.async=false
hotfix.operation=hotfix
hotfix.dlFilePath=/opt/files/foo

inserting contents of one text file into another in bash

If you want to edit a file directly, I always suggest ed instead of the non-standard sed -i (Where different implementions of sed that do support it act differently, a common source of questions here):

printf "%s\n" "/TWO/r ext" w | ed -s base

will insert the contents of file ext after the first line containing TWO in base, and then write the new version of base back to disk.

If you must use sed, the proper invocation will look very similar (No surprise since they're sibling commands):

sed -i '/TWO/r ext' base

(This will insert the ext file after every TWO in base, though, not just the first.)

The key in both is the r command, which reads the contents of the given file and inserts it after a line with the matching address. Works a lot better than trying to read the file contents into a variable and including the text directly in the ed/sed commands.

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If you want to insert the contents of a variable after the line, you can use

printf "%s\n" "/TWO/a" "$ext" . w | ed -s base

(As long as the variable doesn't have a line with just a period)

or with GNU sed

sed -i "/TWO/a ${ext//$'\n'/\\\n}" base

to append text after the addressed line.

Insert content of file at specific line number of another file in LINUX/BASH

You can do it with awk fairly easily using a variable to serve as a flag to only write the contents of tempfile once after the first occurrence of "@type ABCDF". The approach is simple, you output every line with the first {print} rule, then if /@type ABCDF/ && n, you loop with getline reading each line from tempfile and outputting it. When done outputting the file, you simply set n=0 and it will skip all the other occurrences of "@type ABCDF" in the file, e.g.

awk -vn=1 '{print}; /@type ABCDF/ && n{while (getline <"tempfile") print;n=0}' file1 

Example Input file1

$ cat file1
File1
 @type ABCDF #---Insert 'tempfile' content below First occurrence '@type ABCDF'
File2
File3
 @type ABCDF
File4
 @type ABCDF
File5

Example Use/Output

$ awk -vn=1 '{print}; /@type ABCDF/ && n{while (getline <"tempfile") print;n=0}' file1
File1
 @type ABCDF #---Insert 'tempfile' content below First occurrence '@type ABCDF'
tempFile 01
tempFile 02
tempFile 03
tempFile 03
File2
File3
 @type ABCDF
File4
 @type ABCDF
File5

You can redirect the output to a temporary file and then replace the original to emulate an in-place addition of the lines.

Bash: How can I insert a line to a specific location within a file?

This awk should work:

awk  -v a="mysite" '/<VirtualHost /{v=1}
     v && /^ *ServerAlias/{{$0="   ServerAlias " a ".booking.local" RS $0; v=0} 
     /<\/VirtualHost>/{v=0} 1' file

OURPUT:

<VirtualHost *:80>
   ServerName www.sitename.com
   ServerAlias sitename.booking.local
   ServerAlias sitename.com
   DocumentRoot /site/http/travel/itn
   CustomLog logs/access_sitename_log combined
   DirectoryIndex default.php index.php index.html index.phtml index.cgi index.htm
   ScriptAlias /awstats/ /usr/local/awstats/wwwroot/cgi-bin/
   <Directory /site/http/travel/itn >
      AllowOverride All
   </Directory>
</VirtualHost>

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