Adding a line of text to multiple files

Question

So, I have a bunch of files in a directory, and I need to insert a line of text into each of them. They have essentially the following format:

<VirtualHost *:80>
        ServerAdmin gabe@localhost
        DocumentRoot /var/www/test1
        ServerName test1.local
        ServerAlias test1
        <Directory "/var/www/test1">
                Options All
                AllowOverride All
        </Directory>
</VirtualHost>

And I'd like to insert a line before the closing

</VirtualHost>

tag. My first assumption is that I should be able to do this with sed, probably matching and replacing that tag. I'm going to start attempting this now, but if anyone has a existing way to do this, I'd love to hear it.

Answer 1

Something like this:

sed 's/<\/VirtualHost>/yourlinehere\n<\/VirtualHost>/'

works. If you want to repeat this command on a lot of file you can do something like:

for i in *; do sed -i 's/<\/VirtualHost>/yourlinehere\n<\/VirtualHost>/' "$i"; done

Probably better (but untested) thanks to @ChrisDown:

find . -type f -print0 | while IFS= read -r -d '' filename;\
do sed -i 's/<\/VirtualHost>/yourlinehere\n<\/VirtualHost>/' $filename;\ 
done

Answer 2

If you don't mind Perl try:

perl -pi'*.old' -e 's(</VirtualHost>(Your stuff here\n</VirtualHost>)' myfile

The -i switch will save your old file with a .old extension and print to the current one.

Answer 3

You can also use "ex" (command-line vi) if the editing you want to do is even somewhat complicated. For example, you only want to do the insert for on one instance of "".

A shell script like this can work:

for FILENAME in *.whatever  # Need a criteria to glob, or a list of names
do
    ex -s $FILENAME << END_EDITS
/^<\/VirtualHost>/
O " capital-o, not zero
text to insert goes here
.
w!
q
END_EDITS
done

---

This approach gives you the advantages of "ex": finding a location with elaboarte patterns, and 'cursor movements'. You can do things like find a pattern, then find the next instance, THEN do the insert. Or you can change text, rather than just doing inserts. Or you can change between ranges. Don't forget that "ex" lets you use "." as the current line, so .,/^somepatter/s/blah/foo/ will work.